diff --git a/chrome/browser/accessibility/accessibility_extension_api.h b/chrome/browser/accessibility/accessibility_extension_api.h
index 0d21dd3..92765e4 100644
--- a/chrome/browser/accessibility/accessibility_extension_api.h
+++ b/chrome/browser/accessibility/accessibility_extension_api.h
@@ -14,7 +14,7 @@
 
 // API function that enables or disables web content accessibility support.
 class AccessibilityPrivateSetNativeAccessibilityEnabledFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateSetNativeAccessibilityEnabledFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION(
@@ -23,8 +23,7 @@
 };
 
 // API function that sets the location of the accessibility focus ring.
-class AccessibilityPrivateSetFocusRingsFunction
-    : public UIThreadExtensionFunction {
+class AccessibilityPrivateSetFocusRingsFunction : public ExtensionFunction {
   ~AccessibilityPrivateSetFocusRingsFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.setFocusRings",
@@ -32,8 +31,7 @@
 };
 
 // API function that sets the location of the accessibility highlights.
-class AccessibilityPrivateSetHighlightsFunction
-    : public UIThreadExtensionFunction {
+class AccessibilityPrivateSetHighlightsFunction : public ExtensionFunction {
   ~AccessibilityPrivateSetHighlightsFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.setHighlights",
@@ -42,7 +40,7 @@
 
 // API function that sets keyboard capture mode.
 class AccessibilityPrivateSetKeyboardListenerFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateSetKeyboardListenerFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.setKeyboardListener",
@@ -50,8 +48,7 @@
 };
 
 // API function that darkens or undarkens the screen.
-class AccessibilityPrivateDarkenScreenFunction
-    : public UIThreadExtensionFunction {
+class AccessibilityPrivateDarkenScreenFunction : public ExtensionFunction {
   ~AccessibilityPrivateDarkenScreenFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.darkenScreen",
@@ -60,7 +57,7 @@
 
 // Opens a specified subpage in Chrome settings.
 class AccessibilityPrivateOpenSettingsSubpageFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateOpenSettingsSubpageFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.openSettingsSubpage",
@@ -70,7 +67,7 @@
 #if defined(OS_CHROMEOS)
 // API function that sets the keys to be captured by Switch Access.
 class AccessibilityPrivateSetSwitchAccessKeysFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateSetSwitchAccessKeysFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.setSwitchAccessKeys",
@@ -79,7 +76,7 @@
 
 // API function that sets native ChromeVox ARC support.
 class AccessibilityPrivateSetNativeChromeVoxArcSupportForCurrentAppFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateSetNativeChromeVoxArcSupportForCurrentAppFunction()
       override {}
   ResponseAction Run() override;
@@ -90,7 +87,7 @@
 
 // API function that injects key events.
 class AccessibilityPrivateSendSyntheticKeyEventFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateSendSyntheticKeyEventFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.sendSyntheticKeyEvent",
@@ -99,7 +96,7 @@
 
 // API function that enables or disables mouse events in ChromeVox.
 class AccessibilityPrivateEnableChromeVoxMouseEventsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateEnableChromeVoxMouseEventsFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.enableChromeVoxMouseEvents",
@@ -108,7 +105,7 @@
 
 // API function that injects mouse events.
 class AccessibilityPrivateSendSyntheticMouseEventFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateSendSyntheticMouseEventFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.sendSyntheticMouseEvent",
@@ -117,7 +114,7 @@
 
 // API function that is called when the Select-to-Speak extension state changes.
 class AccessibilityPrivateOnSelectToSpeakStateChangedFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateOnSelectToSpeakStateChangedFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.onSelectToSpeakStateChanged",
@@ -127,7 +124,7 @@
 // API function that is called when the Autoclick extension finds scrollable
 // bounds.
 class AccessibilityPrivateOnScrollableBoundsForPointFoundFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateOnScrollableBoundsForPointFoundFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION(
@@ -137,8 +134,7 @@
 
 // API function that is called when a user toggles Dictation from another
 // acessibility feature.
-class AccessibilityPrivateToggleDictationFunction
-    : public UIThreadExtensionFunction {
+class AccessibilityPrivateToggleDictationFunction : public ExtensionFunction {
   ~AccessibilityPrivateToggleDictationFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.toggleDictation",
@@ -147,7 +143,7 @@
 
 // API function that is called to show or hide the Switch Access menu.
 class AccessibilityPrivateSetSwitchAccessMenuStateFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateSetSwitchAccessMenuStateFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.setSwitchAccessMenuState",
@@ -157,7 +153,7 @@
 // API function that requests that key events be forwarded to the Switch
 // Access extension.
 class AccessibilityPrivateForwardKeyEventsToSwitchAccessFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateForwardKeyEventsToSwitchAccessFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION(
@@ -167,7 +163,7 @@
 
 // API function that is called to get the device's battery status as a string.
 class AccessibilityPrivateGetBatteryDescriptionFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   AccessibilityPrivateGetBatteryDescriptionFunction();
   ResponseAction Run() override;
@@ -180,7 +176,7 @@
 
 // API function that opens or closes the virtual keyboard.
 class AccessibilityPrivateSetVirtualKeyboardVisibleFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~AccessibilityPrivateSetVirtualKeyboardVisibleFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("accessibilityPrivate.setVirtualKeyboardVisible",
diff --git a/chrome/browser/apps/platform_apps/api/arc_apps_private/arc_apps_private_api.h b/chrome/browser/apps/platform_apps/api/arc_apps_private/arc_apps_private_api.h
index c0724af..61a7bae 100644
--- a/chrome/browser/apps/platform_apps/api/arc_apps_private/arc_apps_private_api.h
+++ b/chrome/browser/apps/platform_apps/api/arc_apps_private/arc_apps_private_api.h
@@ -52,8 +52,7 @@
   DISALLOW_COPY_AND_ASSIGN(ArcAppsPrivateAPI);
 };
 
-class ArcAppsPrivateGetLaunchableAppsFunction
-    : public UIThreadExtensionFunction {
+class ArcAppsPrivateGetLaunchableAppsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("arcAppsPrivate.getLaunchableApps",
                              ARCAPPSPRIVATE_GETLAUNCHABLEAPPS)
@@ -70,7 +69,7 @@
   DISALLOW_COPY_AND_ASSIGN(ArcAppsPrivateGetLaunchableAppsFunction);
 };
 
-class ArcAppsPrivateLaunchAppFunction : public UIThreadExtensionFunction {
+class ArcAppsPrivateLaunchAppFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("arcAppsPrivate.launchApp",
                              ARCAPPSPRIVATE_LAUNCHAPP)
diff --git a/chrome/browser/apps/platform_apps/api/browser/browser_api.h b/chrome/browser/apps/platform_apps/api/browser/browser_api.h
index 31eaf0e..daa7fa028 100644
--- a/chrome/browser/apps/platform_apps/api/browser/browser_api.h
+++ b/chrome/browser/apps/platform_apps/api/browser/browser_api.h
@@ -10,7 +10,7 @@
 namespace chrome_apps {
 namespace api {
 
-class BrowserOpenTabFunction : public UIThreadExtensionFunction {
+class BrowserOpenTabFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("browser.openTab", BROWSER_OPENTAB)
 
diff --git a/chrome/browser/apps/platform_apps/api/first_run_private/first_run_private_api.h b/chrome/browser/apps/platform_apps/api/first_run_private/first_run_private_api.h
index f9efc2c6..5b099936 100644
--- a/chrome/browser/apps/platform_apps/api/first_run_private/first_run_private_api.h
+++ b/chrome/browser/apps/platform_apps/api/first_run_private/first_run_private_api.h
@@ -12,8 +12,7 @@
 namespace chrome_apps {
 namespace api {
 
-class FirstRunPrivateGetLocalizedStringsFunction
-    : public UIThreadExtensionFunction {
+class FirstRunPrivateGetLocalizedStringsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("firstRunPrivate.getLocalizedStrings",
                              FIRSTRUNPRIVATE_GETLOCALIZEDSTRINGS)
@@ -25,7 +24,7 @@
   ResponseAction Run() override;
 };
 
-class FirstRunPrivateLaunchTutorialFunction : public UIThreadExtensionFunction {
+class FirstRunPrivateLaunchTutorialFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("firstRunPrivate.launchTutorial",
                              FIRSTRUNPRIVATE_LAUNCHTUTORIAL)
diff --git a/chrome/browser/apps/platform_apps/api/music_manager_private/music_manager_private_api.h b/chrome/browser/apps/platform_apps/api/music_manager_private/music_manager_private_api.h
index a726b00..42db857 100644
--- a/chrome/browser/apps/platform_apps/api/music_manager_private/music_manager_private_api.h
+++ b/chrome/browser/apps/platform_apps/api/music_manager_private/music_manager_private_api.h
@@ -10,8 +10,7 @@
 namespace chrome_apps {
 namespace api {
 
-class MusicManagerPrivateGetDeviceIdFunction
-    : public UIThreadExtensionFunction {
+class MusicManagerPrivateGetDeviceIdFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("musicManagerPrivate.getDeviceId",
                              MUSICMANAGERPRIVATE_GETDEVICEID)
@@ -21,7 +20,7 @@
  protected:
   ~MusicManagerPrivateGetDeviceIdFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
   void DeviceIdCallback(const std::string& device_id);
diff --git a/chrome/browser/apps/platform_apps/api/sync_file_system/sync_file_system_api.h b/chrome/browser/apps/platform_apps/api/sync_file_system/sync_file_system_api.h
index 45f2b4e..1bcfe19 100644
--- a/chrome/browser/apps/platform_apps/api/sync_file_system/sync_file_system_api.h
+++ b/chrome/browser/apps/platform_apps/api/sync_file_system/sync_file_system_api.h
@@ -122,7 +122,7 @@
 };
 
 class SyncFileSystemSetConflictResolutionPolicyFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("syncFileSystem.setConflictResolutionPolicy",
                              SYNCFILESYSTEM_SETCONFLICTRESOLUTIONPOLICY)
@@ -133,7 +133,7 @@
 };
 
 class SyncFileSystemGetConflictResolutionPolicyFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("syncFileSystem.getConflictResolutionPolicy",
                              SYNCFILESYSTEM_GETCONFLICTRESOLUTIONPOLICY)
@@ -143,8 +143,7 @@
   ResponseAction Run() override;
 };
 
-class SyncFileSystemGetServiceStatusFunction
-    : public UIThreadExtensionFunction {
+class SyncFileSystemGetServiceStatusFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("syncFileSystem.getServiceStatus",
                              SYNCFILESYSTEM_GETSERVICESTATUS)
diff --git a/chrome/browser/apps/platform_apps/api/webstore_widget_private/webstore_widget_private_api.h b/chrome/browser/apps/platform_apps/api/webstore_widget_private/webstore_widget_private_api.h
index 9d1aa430..47f80853 100644
--- a/chrome/browser/apps/platform_apps/api/webstore_widget_private/webstore_widget_private_api.h
+++ b/chrome/browser/apps/platform_apps/api/webstore_widget_private/webstore_widget_private_api.h
@@ -15,7 +15,7 @@
 namespace api {
 
 class WebstoreWidgetPrivateInstallWebstoreItemFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   WebstoreWidgetPrivateInstallWebstoreItemFunction();
 
@@ -25,7 +25,7 @@
  protected:
   ~WebstoreWidgetPrivateInstallWebstoreItemFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
diff --git a/chrome/browser/chromeos/extensions/autotest_private/autotest_private_api.h b/chrome/browser/chromeos/extensions/autotest_private/autotest_private_api.h
index cee74821..3bfc0f8 100644
--- a/chrome/browser/chromeos/extensions/autotest_private/autotest_private_api.h
+++ b/chrome/browser/chromeos/extensions/autotest_private/autotest_private_api.h
@@ -28,7 +28,7 @@
 
 namespace extensions {
 
-class AutotestPrivateLogoutFunction : public UIThreadExtensionFunction {
+class AutotestPrivateLogoutFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.logout", AUTOTESTPRIVATE_LOGOUT)
 
@@ -37,7 +37,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateRestartFunction : public UIThreadExtensionFunction {
+class AutotestPrivateRestartFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.restart", AUTOTESTPRIVATE_RESTART)
 
@@ -46,7 +46,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateShutdownFunction : public UIThreadExtensionFunction {
+class AutotestPrivateShutdownFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.shutdown",
                              AUTOTESTPRIVATE_SHUTDOWN)
@@ -56,7 +56,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateLoginStatusFunction : public UIThreadExtensionFunction {
+class AutotestPrivateLoginStatusFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.loginStatus",
                              AUTOTESTPRIVATE_LOGINSTATUS)
@@ -66,7 +66,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateLockScreenFunction : public UIThreadExtensionFunction {
+class AutotestPrivateLockScreenFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.lockScreen",
                              AUTOTESTPRIVATE_LOCKSCREEN)
@@ -76,8 +76,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateGetExtensionsInfoFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateGetExtensionsInfoFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getExtensionsInfo",
                              AUTOTESTPRIVATE_GETEXTENSIONSINFO)
@@ -87,8 +86,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSimulateAsanMemoryBugFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSimulateAsanMemoryBugFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.simulateAsanMemoryBug",
                              AUTOTESTPRIVATE_SIMULATEASANMEMORYBUG)
@@ -98,8 +96,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetTouchpadSensitivityFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetTouchpadSensitivityFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setTouchpadSensitivity",
                              AUTOTESTPRIVATE_SETTOUCHPADSENSITIVITY)
@@ -109,7 +106,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetTapToClickFunction : public UIThreadExtensionFunction {
+class AutotestPrivateSetTapToClickFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setTapToClick",
                              AUTOTESTPRIVATE_SETTAPTOCLICK)
@@ -119,8 +116,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetThreeFingerClickFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetThreeFingerClickFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setThreeFingerClick",
                              AUTOTESTPRIVATE_SETTHREEFINGERCLICK)
@@ -130,7 +126,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetTapDraggingFunction : public UIThreadExtensionFunction {
+class AutotestPrivateSetTapDraggingFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setTapDragging",
                              AUTOTESTPRIVATE_SETTAPDRAGGING)
@@ -140,8 +136,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetNaturalScrollFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetNaturalScrollFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setNaturalScroll",
                              AUTOTESTPRIVATE_SETNATURALSCROLL)
@@ -151,8 +146,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetMouseSensitivityFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetMouseSensitivityFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setMouseSensitivity",
                              AUTOTESTPRIVATE_SETMOUSESENSITIVITY)
@@ -162,8 +156,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetPrimaryButtonRightFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetPrimaryButtonRightFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setPrimaryButtonRight",
                              AUTOTESTPRIVATE_SETPRIMARYBUTTONRIGHT)
@@ -173,8 +166,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetMouseReverseScrollFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetMouseReverseScrollFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setMouseReverseScroll",
                              AUTOTESTPRIVATE_SETMOUSEREVERSESCROLL)
@@ -185,7 +177,7 @@
 };
 
 class AutotestPrivateGetVisibleNotificationsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   AutotestPrivateGetVisibleNotificationsFunction();
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getVisibleNotifications",
@@ -196,8 +188,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateGetPlayStoreStateFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateGetPlayStoreStateFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getPlayStoreState",
                              AUTOTESTPRIVATE_GETPLAYSTORESTATE)
@@ -207,7 +198,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateGetArcStateFunction : public UIThreadExtensionFunction {
+class AutotestPrivateGetArcStateFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getArcState",
                              AUTOTESTPRIVATE_GETARCSTATE)
@@ -217,8 +208,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetPlayStoreEnabledFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetPlayStoreEnabledFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setPlayStoreEnabled",
                              AUTOTESTPRIVATE_SETPLAYSTOREENABLED)
@@ -228,7 +218,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateGetHistogramFunction : public UIThreadExtensionFunction {
+class AutotestPrivateGetHistogramFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getHistogram",
                              AUTOTESTPRIVATE_GETHISTOGRAM)
@@ -246,7 +236,7 @@
   ResponseValue GetHistogram(const std::string& name);
 };
 
-class AutotestPrivateIsAppShownFunction : public UIThreadExtensionFunction {
+class AutotestPrivateIsAppShownFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.isAppShown",
                              AUTOTESTPRIVATE_ISAPPSHOWN)
@@ -257,8 +247,7 @@
 };
 
 // Deprecated, use GetArcState instead.
-class AutotestPrivateIsArcProvisionedFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateIsArcProvisionedFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.isArcProvisioned",
                              AUTOTESTPRIVATE_ISARCPROVISIONED)
@@ -268,7 +257,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateGetArcAppFunction : public UIThreadExtensionFunction {
+class AutotestPrivateGetArcAppFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getArcApp",
                              AUTOTESTPRIVATE_GETARCAPP)
@@ -278,7 +267,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateGetArcPackageFunction : public UIThreadExtensionFunction {
+class AutotestPrivateGetArcPackageFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getArcPackage",
                              AUTOTESTPRIVATE_GETARCPACKAGE)
@@ -288,7 +277,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateLaunchArcAppFunction : public UIThreadExtensionFunction {
+class AutotestPrivateLaunchArcAppFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.launchArcApp",
                              AUTOTESTPRIVATE_LAUNCHARCAPP)
@@ -298,7 +287,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateLaunchAppFunction : public UIThreadExtensionFunction {
+class AutotestPrivateLaunchAppFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.launchApp",
                              AUTOTESTPRIVATE_LAUNCHAPP)
@@ -308,7 +297,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateCloseAppFunction : public UIThreadExtensionFunction {
+class AutotestPrivateCloseAppFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.closeApp",
                              AUTOTESTPRIVATE_CLOSEAPP)
@@ -318,8 +307,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetCrostiniEnabledFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetCrostiniEnabledFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setCrostiniEnabled",
                              AUTOTESTPRIVATE_SETCROSTINIENABLED)
@@ -329,8 +317,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateRunCrostiniInstallerFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateRunCrostiniInstallerFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.runCrostiniInstaller",
                              AUTOTESTPRIVATE_RUNCROSTINIINSTALLER)
@@ -342,8 +329,7 @@
   void CrostiniRestarted(crostini::CrostiniResult);
 };
 
-class AutotestPrivateRunCrostiniUninstallerFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateRunCrostiniUninstallerFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.runCrostiniUninstaller",
                              AUTOTESTPRIVATE_RUNCROSTINIUNINSTALLER)
@@ -355,7 +341,7 @@
   void CrostiniRemoved(crostini::CrostiniResult);
 };
 
-class AutotestPrivateExportCrostiniFunction : public UIThreadExtensionFunction {
+class AutotestPrivateExportCrostiniFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.exportCrostini",
                              AUTOTESTPRIVATE_EXPORTCROSTINI)
@@ -367,7 +353,7 @@
   void CrostiniExported(crostini::CrostiniResult);
 };
 
-class AutotestPrivateImportCrostiniFunction : public UIThreadExtensionFunction {
+class AutotestPrivateImportCrostiniFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.importCrostini",
                              AUTOTESTPRIVATE_IMPORTCROSTINI)
@@ -379,7 +365,7 @@
   void CrostiniImported(crostini::CrostiniResult);
 };
 
-class AutotestPrivateTakeScreenshotFunction : public UIThreadExtensionFunction {
+class AutotestPrivateTakeScreenshotFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.takeScreenshot",
                              AUTOTESTPRIVATE_TAKESCREENSHOT)
@@ -394,7 +380,7 @@
 };
 
 class AutotestPrivateGetPrinterListFunction
-    : public UIThreadExtensionFunction,
+    : public ExtensionFunction,
       public chromeos::CupsPrintersManager::Observer {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getPrinterList",
@@ -413,7 +399,7 @@
   base::OneShotTimer timeout_timer_;
 };
 
-class AutotestPrivateUpdatePrinterFunction : public UIThreadExtensionFunction {
+class AutotestPrivateUpdatePrinterFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.updatePrinter",
                              AUTOTESTPRIVATE_UPDATEPRINTER)
@@ -423,7 +409,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateRemovePrinterFunction : public UIThreadExtensionFunction {
+class AutotestPrivateRemovePrinterFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.removePrinter",
                              AUTOTESTPRIVATE_REMOVEPRINTER)
@@ -434,7 +420,7 @@
 };
 
 class AutotestPrivateGetAllEnterprisePoliciesFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getAllEnterprisePolicies",
                              AUTOTESTPRIVATE_GETALLENTERPRISEPOLICIES)
@@ -445,7 +431,7 @@
 };
 
 class AutotestPrivateBootstrapMachineLearningServiceFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   AutotestPrivateBootstrapMachineLearningServiceFunction();
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.bootstrapMachineLearningService",
@@ -465,7 +451,7 @@
 // Enable/disable the Google Assistant feature. This toggles the Assistant user
 // pref which will indirectly bring up or shut down the Assistant service.
 class AutotestPrivateSetAssistantEnabledFunction
-    : public UIThreadExtensionFunction,
+    : public ExtensionFunction,
       public ash::DefaultVoiceInteractionObserver {
  public:
   AutotestPrivateSetAssistantEnabledFunction();
@@ -491,7 +477,7 @@
 
 // Send text query to Assistant and return response.
 class AutotestPrivateSendAssistantTextQueryFunction
-    : public UIThreadExtensionFunction,
+    : public ExtensionFunction,
       public chromeos::assistant::mojom::AssistantInteractionSubscriber {
  public:
   AutotestPrivateSendAssistantTextQueryFunction();
@@ -540,8 +526,7 @@
 };
 
 // Set user pref value in the pref tree.
-class AutotestPrivateSetWhitelistedPrefFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetWhitelistedPrefFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setWhitelistedPref",
                              AUTOTESTPRIVATE_SETWHITELISTEDPREF)
@@ -553,8 +538,7 @@
 
 // Enable/disable a Crostini app's "scaled" property.
 // When an app is "scaled", it will use low display density.
-class AutotestPrivateSetCrostiniAppScaledFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetCrostiniAppScaledFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setCrostiniAppScaled",
                              AUTOTESTPRIVATE_SETCROSTINIAPPSCALED)
@@ -589,7 +573,7 @@
 
 // Get the primary display's scale factor.
 class AutotestPrivateGetPrimaryDisplayScaleFactorFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getPrimaryDisplayScaleFactor",
                              AUTOTESTPRIVATE_GETPRIMARYDISPLAYSCALEFACTOR)
@@ -599,8 +583,7 @@
 };
 
 // Returns if tablet mode is enabled.
-class AutotestPrivateIsTabletModeEnabledFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateIsTabletModeEnabledFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.isTabletModeEnabled",
                              AUTOTESTPRIVATE_ISTABLETMODEENABLED)
@@ -610,8 +593,7 @@
 };
 
 // Enables/Disables tablet mode.
-class AutotestPrivateSetTabletModeEnabledFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetTabletModeEnabledFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setTabletModeEnabled",
                              AUTOTESTPRIVATE_SETTABLETMODEENABLED)
@@ -623,7 +605,7 @@
 
 // Returns the shelf auto hide behavior.
 class AutotestPrivateGetShelfAutoHideBehaviorFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   AutotestPrivateGetShelfAutoHideBehaviorFunction();
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getShelfAutoHideBehavior",
@@ -636,7 +618,7 @@
 
 // Sets shelf autohide behavior.
 class AutotestPrivateSetShelfAutoHideBehaviorFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   AutotestPrivateSetShelfAutoHideBehaviorFunction();
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setShelfAutoHideBehavior",
@@ -648,8 +630,7 @@
 };
 
 // Returns the shelf alignment.
-class AutotestPrivateGetShelfAlignmentFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateGetShelfAlignmentFunction : public ExtensionFunction {
  public:
   AutotestPrivateGetShelfAlignmentFunction();
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.getShelfAlignment",
@@ -661,8 +642,7 @@
 };
 
 // Sets shelf alignment.
-class AutotestPrivateSetShelfAlignmentFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetShelfAlignmentFunction : public ExtensionFunction {
  public:
   AutotestPrivateSetShelfAlignmentFunction();
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setShelfAlignment",
@@ -674,7 +654,7 @@
 };
 
 class AutotestPrivateShowVirtualKeyboardIfEnabledFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   AutotestPrivateShowVirtualKeyboardIfEnabledFunction();
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.showVirtualKeyboardIfEnabled",
@@ -685,8 +665,7 @@
   ResponseAction Run() override;
 };
 
-class AutotestPrivateSetArcAppWindowStateFunction
-    : public UIThreadExtensionFunction {
+class AutotestPrivateSetArcAppWindowStateFunction : public ExtensionFunction {
  public:
   AutotestPrivateSetArcAppWindowStateFunction();
   DECLARE_EXTENSION_FUNCTION("autotestPrivate.setArcAppWindowState",
diff --git a/chrome/browser/chromeos/extensions/echo_private_api.h b/chrome/browser/chromeos/extensions/echo_private_api.h
index 60302f57..0e00caa9 100644
--- a/chrome/browser/chromeos/extensions/echo_private_api.h
+++ b/chrome/browser/chromeos/extensions/echo_private_api.h
@@ -26,8 +26,7 @@
 
 }  // namespace chromeos
 
-class EchoPrivateGetRegistrationCodeFunction
-    : public UIThreadExtensionFunction {
+class EchoPrivateGetRegistrationCodeFunction : public ExtensionFunction {
  public:
   EchoPrivateGetRegistrationCodeFunction();
 
@@ -56,7 +55,7 @@
                              ECHOPRIVATE_GETOOBETIMESTAMP)
 };
 
-class EchoPrivateSetOfferInfoFunction : public UIThreadExtensionFunction {
+class EchoPrivateSetOfferInfoFunction : public ExtensionFunction {
  public:
   EchoPrivateSetOfferInfoFunction();
 
@@ -69,7 +68,7 @@
                              ECHOPRIVATE_SETOFFERINFO)
 };
 
-class EchoPrivateGetOfferInfoFunction : public UIThreadExtensionFunction {
+class EchoPrivateGetOfferInfoFunction : public ExtensionFunction {
  public:
   EchoPrivateGetOfferInfoFunction();
 
diff --git a/chrome/browser/chromeos/extensions/file_manager/file_browser_handler_api.h b/chrome/browser/chromeos/extensions/file_manager/file_browser_handler_api.h
index b892577..bbe7cc8c 100644
--- a/chrome/browser/chromeos/extensions/file_manager/file_browser_handler_api.h
+++ b/chrome/browser/chromeos/extensions/file_manager/file_browser_handler_api.h
@@ -81,7 +81,7 @@
 // The fileBrowserHandlerInternal.selectFile extension function implementation.
 // See the file description for more info.
 class FileBrowserHandlerInternalSelectFileFunction
-    : public extensions::LoggedUIThreadExtensionFunction {
+    : public extensions::LoggedExtensionFunction {
  public:
   // Default constructor used in production code.
   // It will create its own FileSelectorFactory implementation, and set the
@@ -108,7 +108,7 @@
   // The class is ref counted, so destructor should not be public.
   ~FileBrowserHandlerInternalSelectFileFunction() override;
 
-  // UIThreadExtensionFunction implementation.
+  // ExtensionFunction implementation.
   // Runs the extension function implementation.
   ResponseAction Run() override;
 
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_base.cc b/chrome/browser/chromeos/extensions/file_manager/private_api_base.cc
index 581d480..42eec842 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_base.cc
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_base.cc
@@ -22,16 +22,16 @@
 
 }  // namespace
 
-LoggedUIThreadExtensionFunction::LoggedUIThreadExtensionFunction()
+LoggedExtensionFunction::LoggedExtensionFunction()
     : log_on_completion_(false),
       slow_threshold_(kDefaultSlowOperationThreshold),
       very_slow_threshold_(kDefaultVerySlowOperationThreshold) {
   start_time_ = base::TimeTicks::Now();
 }
 
-LoggedUIThreadExtensionFunction::~LoggedUIThreadExtensionFunction() = default;
+LoggedExtensionFunction::~LoggedExtensionFunction() = default;
 
-void LoggedUIThreadExtensionFunction::OnResponded() {
+void LoggedExtensionFunction::OnResponded() {
   base::TimeDelta elapsed = base::TimeTicks::Now() - start_time_;
 
   const ChromeExtensionFunctionDetails chrome_details(this);
@@ -61,10 +61,10 @@
                 "ms)",
                 name(), request_id(), elapsed.InMilliseconds());
   }
-  UIThreadExtensionFunction::OnResponded();
+  ExtensionFunction::OnResponded();
 }
 
-void LoggedUIThreadExtensionFunction::SetWarningThresholds(
+void LoggedExtensionFunction::SetWarningThresholds(
     base::TimeDelta slow_threshold,
     base::TimeDelta very_slow_threshold) {
   slow_threshold_ = slow_threshold;
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_base.h b/chrome/browser/chromeos/extensions/file_manager/private_api_base.h
index bf5cd6ce..28423ff3 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_base.h
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_base.h
@@ -12,7 +12,7 @@
 
 namespace extensions {
 
-// This class adds a logging feature to UIThreadExtensionFunction. Logging is
+// This class adds a logging feature to ExtensionFunction. Logging is
 // done when sending the response to JavaScript, using drive::util::Log().
 // API functions of fileManagerPrivate should inherit this class.
 //
@@ -20,14 +20,14 @@
 // set_log_on_completion(true) to enable it, if they want. However, even if
 // the logging is turned off, a warning is emitted when a function call is
 // very slow. See the implementation of OnResponded() for details.
-class LoggedUIThreadExtensionFunction : public UIThreadExtensionFunction {
+class LoggedExtensionFunction : public ExtensionFunction {
  public:
-  LoggedUIThreadExtensionFunction();
+  LoggedExtensionFunction();
 
  protected:
-  ~LoggedUIThreadExtensionFunction() override;
+  ~LoggedExtensionFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   void OnResponded() override;
 
   void SetWarningThresholds(base::TimeDelta slow_threshold,
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_dialog.cc b/chrome/browser/chromeos/extensions/file_manager/private_api_dialog.cc
index 1832a21..712b09d 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_dialog.cc
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_dialog.cc
@@ -31,7 +31,7 @@
 
 // Computes the routing ID for SelectFileDialogExtension from the |function|.
 SelectFileDialogExtension::RoutingID GetFileDialogRoutingID(
-    UIThreadExtensionFunction* function) {
+    ExtensionFunction* function) {
   return SelectFileDialogExtensionUserData::GetRoutingIdForWebContents(
       function->GetSenderWebContents());
 }
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_dialog.h b/chrome/browser/chromeos/extensions/file_manager/private_api_dialog.h
index 492bb28..6bfcf7a 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_dialog.h
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_dialog.h
@@ -21,8 +21,7 @@
 namespace extensions {
 
 // Cancel file selection Dialog.  Closes the dialog window.
-class FileManagerPrivateCancelDialogFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateCancelDialogFunction : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.cancelDialog",
                              FILEMANAGERPRIVATE_CANCELDIALOG)
@@ -34,8 +33,7 @@
   ResponseAction Run() override;
 };
 
-class FileManagerPrivateSelectFileFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateSelectFileFunction : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.selectFile",
                              FILEMANAGERPRIVATE_SELECTFILE)
@@ -55,8 +53,7 @@
 };
 
 // Select multiple files.  Closes the dialog window.
-class FileManagerPrivateSelectFilesFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateSelectFilesFunction : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.selectFiles",
                              FILEMANAGERPRIVATE_SELECTFILES)
@@ -76,7 +73,7 @@
 
 // Get a list of Android picker apps.
 class FileManagerPrivateGetAndroidPickerAppsFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.getAndroidPickerApps",
                              FILEMANAGERPRIVATE_GETANDROIDPICKERAPPS)
@@ -97,7 +94,7 @@
 
 // Select an Android picker app.  Closes the dialog window.
 class FileManagerPrivateSelectAndroidPickerAppFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.selectAndroidPickerApp",
                              FILEMANAGERPRIVATE_SELECTANDROIDPICKERAPP)
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_drive.cc b/chrome/browser/chromeos/extensions/file_manager/private_api_drive.cc
index c65b8493..9da60d8 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_drive.cc
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_drive.cc
@@ -861,7 +861,7 @@
 }
 
 void OnSearchDriveFs(
-    scoped_refptr<UIThreadExtensionFunction> function,
+    scoped_refptr<ExtensionFunction> function,
     bool filter_dirs,
     base::OnceCallback<void(std::unique_ptr<base::ListValue>)> callback,
     drive::FileError error,
@@ -911,7 +911,7 @@
 }
 
 drivefs::mojom::QueryParameters::QuerySource SearchDriveFs(
-    scoped_refptr<UIThreadExtensionFunction> function,
+    scoped_refptr<ExtensionFunction> function,
     drivefs::mojom::QueryParametersPtr query,
     bool filter_dirs,
     base::OnceCallback<void(std::unique_ptr<base::ListValue>)> callback) {
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_drive.h b/chrome/browser/chromeos/extensions/file_manager/private_api_drive.h
index 7795a90..65f69753 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_drive.h
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_drive.h
@@ -39,7 +39,7 @@
 
 // Implements the chrome.fileManagerPrivate.ensureFileDownloaded method.
 class FileManagerPrivateInternalEnsureFileDownloadedFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalEnsureFileDownloadedFunction();
 
@@ -63,7 +63,7 @@
 // On error, returns a dictionary with the key "error" set to the error number
 // (base::File::Error).
 class FileManagerPrivateInternalGetEntryPropertiesFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.getEntryProperties",
                              FILEMANAGERPRIVATEINTERNAL_GETENTRYPROPERTIES)
@@ -89,7 +89,7 @@
 
 // Implements the chrome.fileManagerPrivate.pinDriveFile method.
 class FileManagerPrivateInternalPinDriveFileFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalPinDriveFileFunction();
 
@@ -114,7 +114,7 @@
 
 // Implements the chrome.fileManagerPrivate.cancelFileTransfers method.
 class FileManagerPrivateInternalCancelFileTransfersFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.cancelFileTransfers",
                              FILEMANAGERPRIVATEINTERNAL_CANCELFILETRANSFERS)
@@ -126,8 +126,7 @@
   ResponseAction Run() override;
 };
 
-class FileManagerPrivateSearchDriveFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateSearchDriveFunction : public LoggedExtensionFunction {
  public:
   typedef std::vector<drive::SearchResultInfo> SearchResultInfoList;
 
@@ -165,7 +164,7 @@
 // Similar to FileManagerPrivateSearchDriveFunction but this one is used for
 // searching drive metadata which is stored locally.
 class FileManagerPrivateSearchDriveMetadataFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   enum class SearchType {
     kText,
@@ -207,7 +206,7 @@
 
 // Implements the chrome.fileManagerPrivate.getDriveConnectionState method.
 class FileManagerPrivateGetDriveConnectionStateFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.getDriveConnectionState",
                              FILEMANAGERPRIVATE_GETDRIVECONNECTIONSTATE)
@@ -220,7 +219,7 @@
 
 // Implements the chrome.fileManagerPrivate.requestAccessToken method.
 class FileManagerPrivateRequestAccessTokenFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateRequestAccessTokenFunction();
 
@@ -240,7 +239,7 @@
 
 // Implements the chrome.fileManagerPrivate.requestDriveShare method.
 class FileManagerPrivateInternalRequestDriveShareFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalRequestDriveShareFunction();
 
@@ -258,7 +257,7 @@
 
 // Implements the chrome.fileManagerPrivate.getDownloadUrl method.
 class FileManagerPrivateInternalGetDownloadUrlFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalGetDownloadUrlFunction();
 
@@ -295,7 +294,7 @@
 };
 
 class FileManagerPrivateInternalGetThumbnailFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.getThumbnail",
                              FILEMANAGERPRIVATEINTERNAL_GETTHUMBNAIL)
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_file_system.h b/chrome/browser/chromeos/extensions/file_manager/private_api_file_system.h
index e03f7f2d..69f82140 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_file_system.h
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_file_system.h
@@ -51,7 +51,7 @@
 // Grant permission to request externalfile scheme. The permission is needed to
 // start drag for external file URL.
 class FileManagerPrivateEnableExternalFileSchemeFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.enableExternalFileScheme",
                              FILEMANAGERPRIVATE_ENABLEEXTERNALFILESCHEME)
@@ -65,7 +65,7 @@
 
 // Grants R/W permissions to profile-specific directories (Drive, Downloads)
 // from other profiles.
-class FileManagerPrivateGrantAccessFunction : public UIThreadExtensionFunction {
+class FileManagerPrivateGrantAccessFunction : public ExtensionFunction {
  public:
   FileManagerPrivateGrantAccessFunction();
 
@@ -86,7 +86,7 @@
 // "FileWatch",
 // the class and its sub classes are used only for watching changes in
 // directories.
-class FileWatchFunctionBase : public LoggedUIThreadExtensionFunction {
+class FileWatchFunctionBase : public LoggedExtensionFunction {
  public:
   using ResponseCallback = base::Callback<void(bool success)>;
 
@@ -167,8 +167,7 @@
 };
 
 // Implements the chrome.fileManagerPrivate.getSizeStats method.
-class FileManagerPrivateGetSizeStatsFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateGetSizeStatsFunction : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.getSizeStats",
                              FILEMANAGERPRIVATE_GETSIZESTATS)
@@ -193,7 +192,7 @@
 
 // Implements the chrome.fileManagerPrivate.validatePathNameLength method.
 class FileManagerPrivateInternalValidatePathNameLengthFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION(
       "fileManagerPrivateInternal.validatePathNameLength",
@@ -211,8 +210,7 @@
 
 // Implements the chrome.fileManagerPrivate.formatVolume method.
 // Formats Volume given its mount path.
-class FileManagerPrivateFormatVolumeFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateFormatVolumeFunction : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.formatVolume",
                              FILEMANAGERPRIVATE_FORMATVOLUME)
@@ -226,8 +224,7 @@
 
 // Implements the chrome.fileManagerPrivate.renameVolume method.
 // Renames Volume given its mount path and new Volume name.
-class FileManagerPrivateRenameVolumeFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateRenameVolumeFunction : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.renameVolume",
                              FILEMANAGERPRIVATE_RENAMEVOLUME)
@@ -241,7 +238,7 @@
 
 // Implements the chrome.fileManagerPrivate.startCopy method.
 class FileManagerPrivateInternalStartCopyFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalStartCopyFunction();
 
@@ -276,8 +273,7 @@
 };
 
 // Implements the chrome.fileManagerPrivate.cancelCopy method.
-class FileManagerPrivateCancelCopyFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateCancelCopyFunction : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.cancelCopy",
                              FILEMANAGERPRIVATE_CANCELCOPY)
@@ -292,7 +288,7 @@
 // Implements the chrome.fileManagerPrivateInternal.resolveIsolatedEntries
 // method.
 class FileManagerPrivateInternalResolveIsolatedEntriesFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION(
       "fileManagerPrivateInternal.resolveIsolatedEntries",
@@ -302,7 +298,7 @@
   ~FileManagerPrivateInternalResolveIsolatedEntriesFunction() override =
       default;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
@@ -312,7 +308,7 @@
 };
 
 class FileManagerPrivateInternalComputeChecksumFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalComputeChecksumFunction();
 
@@ -334,7 +330,7 @@
 // Implements the chrome.fileManagerPrivate.searchFilesByHashes method.
 // TODO(b/883628): Write some tests maybe?
 class FileManagerPrivateSearchFilesByHashesFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateSearchFilesByHashesFunction();
 
@@ -364,8 +360,7 @@
   const ChromeExtensionFunctionDetails chrome_details_;
 };
 
-class FileManagerPrivateSearchFilesFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateSearchFilesFunction : public LoggedExtensionFunction {
  public:
   FileManagerPrivateSearchFilesFunction();
 
@@ -387,7 +382,7 @@
 
 // Implements the chrome.fileManagerPrivate.setEntryTag method.
 class FileManagerPrivateInternalSetEntryTagFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalSetEntryTagFunction();
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.setEntryTag",
@@ -407,7 +402,7 @@
 
 // Implements the chrome.fileManagerPrivate.getDirectorySize method.
 class FileManagerPrivateInternalGetDirectorySizeFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.getDirectorySize",
                              FILEMANAGERPRIVATEINTERNAL_GETDIRECTORYSIZE)
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_misc.cc b/chrome/browser/chromeos/extensions/file_manager/private_api_misc.cc
index 3fa8f58..2e57b06e 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_misc.cc
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_misc.cc
@@ -93,7 +93,7 @@
     base::TimeDelta::FromSeconds(30);
 
 // Obtains the current app window.
-AppWindow* GetCurrentAppWindow(UIThreadExtensionFunction* function) {
+AppWindow* GetCurrentAppWindow(ExtensionFunction* function) {
   content::WebContents* const contents = function->GetSenderWebContents();
   return contents
              ? AppWindowRegistry::Get(function->browser_context())
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_misc.h b/chrome/browser/chromeos/extensions/file_manager/private_api_misc.h
index 8ba79a4..42eb24fd5 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_misc.h
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_misc.h
@@ -46,7 +46,7 @@
 // Implements the chrome.fileManagerPrivate.logoutUserForReauthentication
 // method.
 class FileManagerPrivateLogoutUserForReauthenticationFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.logoutUserForReauthentication",
                              FILEMANAGERPRIVATE_LOGOUTUSERFORREAUTHENTICATION)
@@ -60,8 +60,7 @@
 
 // Implements the chrome.fileManagerPrivate.getPreferences method.
 // Gets settings for the Files app.
-class FileManagerPrivateGetPreferencesFunction
-    : public UIThreadExtensionFunction {
+class FileManagerPrivateGetPreferencesFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.getPreferences",
                              FILEMANAGERPRIVATE_GETPREFERENCES)
@@ -74,8 +73,7 @@
 
 // Implements the chrome.fileManagerPrivate.setPreferences method.
 // Sets settings for the Files app.
-class FileManagerPrivateSetPreferencesFunction
-    : public UIThreadExtensionFunction {
+class FileManagerPrivateSetPreferencesFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.setPreferences",
                              FILEMANAGERPRIVATE_SETPREFERENCES)
@@ -90,7 +88,7 @@
 // Sets the ARC flag for the Files app and returns what was the state before
 // setting.
 class FileManagerPrivateSetArcStorageToastShownFlagFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.setArcStorageToastShownFlag",
                              FILEMANAGERPRIVATE_SETARCSTORAGETOASTSHOWNFLAG)
@@ -104,7 +102,7 @@
 // Implements the chrome.fileManagerPrivate.zipSelection method.
 // Creates a zip file for the selected files.
 class FileManagerPrivateInternalZipSelectionFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.zipSelection",
                              FILEMANAGERPRIVATEINTERNAL_ZIPSELECTION)
@@ -126,7 +124,7 @@
 // WebContents.
 // TODO(hirono): Remove this function once the zoom level change is supported
 // for all apps. crbug.com/227175.
-class FileManagerPrivateZoomFunction : public UIThreadExtensionFunction {
+class FileManagerPrivateZoomFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.zoom", FILEMANAGERPRIVATE_ZOOM)
 
@@ -138,7 +136,7 @@
 };
 
 class FileManagerPrivateRequestWebStoreAccessTokenFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.requestWebStoreAccessToken",
                              FILEMANAGERPRIVATE_REQUESTWEBSTOREACCESSTOKEN)
@@ -159,7 +157,7 @@
   const ChromeExtensionFunctionDetails chrome_details_;
 };
 
-class FileManagerPrivateGetProfilesFunction : public UIThreadExtensionFunction {
+class FileManagerPrivateGetProfilesFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.getProfiles",
                              FILEMANAGERPRIVATE_GETPROFILES)
@@ -172,8 +170,7 @@
 };
 
 // Implements the chrome.fileManagerPrivate.openInspector method.
-class FileManagerPrivateOpenInspectorFunction
-    : public UIThreadExtensionFunction {
+class FileManagerPrivateOpenInspectorFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.openInspector",
                              FILEMANAGERPRIVATE_OPENINSPECTOR)
@@ -185,8 +182,7 @@
 };
 
 // Implements the chrome.fileManagerPrivate.openSettingsSubpage method.
-class FileManagerPrivateOpenSettingsSubpageFunction
-    : public UIThreadExtensionFunction {
+class FileManagerPrivateOpenSettingsSubpageFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.openSettingsSubpage",
                              FILEMANAGERPRIVATE_OPENSETTINGSSUBPAGE)
@@ -199,7 +195,7 @@
 
 // Implements the chrome.fileManagerPrivate.getMimeType method.
 class FileManagerPrivateInternalGetMimeTypeFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.getMimeType",
                              FILEMANAGERPRIVATEINTERNAL_GETMIMETYPE)
@@ -216,8 +212,7 @@
 };
 
 // Implements the chrome.fileManagerPrivate.isPiexLoaderEnabled method.
-class FileManagerPrivateIsPiexLoaderEnabledFunction
-    : public UIThreadExtensionFunction {
+class FileManagerPrivateIsPiexLoaderEnabledFunction : public ExtensionFunction {
  public:
   FileManagerPrivateIsPiexLoaderEnabledFunction() = default;
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.isPiexLoaderEnabled",
@@ -231,8 +226,7 @@
 };
 
 // Implements the chrome.fileManagerPrivate.getProviders method.
-class FileManagerPrivateGetProvidersFunction
-    : public UIThreadExtensionFunction {
+class FileManagerPrivateGetProvidersFunction : public ExtensionFunction {
  public:
   FileManagerPrivateGetProvidersFunction();
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.getProviders",
@@ -248,7 +242,7 @@
 
 // Implements the chrome.fileManagerPrivate.addProvidedFileSystem method.
 class FileManagerPrivateAddProvidedFileSystemFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   FileManagerPrivateAddProvidedFileSystemFunction();
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.addProvidedFileSystem",
@@ -264,7 +258,7 @@
 
 // Implements the chrome.fileManagerPrivate.configureVolume method.
 class FileManagerPrivateConfigureVolumeFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateConfigureVolumeFunction();
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.configureVolume",
@@ -282,8 +276,7 @@
 
 // Implements the chrome.fileManagerPrivate.mountCrostini method.
 // Starts and mounts crostini container.
-class FileManagerPrivateMountCrostiniFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateMountCrostiniFunction : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.mountCrostini",
                              FILEMANAGERPRIVATE_MOUNTCROSTINI)
@@ -304,7 +297,7 @@
 // Implements the chrome.fileManagerPrivate.sharePathsWithCrostini
 // method.  Shares specified paths.
 class FileManagerPrivateInternalSharePathsWithCrostiniFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION(
       "fileManagerPrivateInternal.sharePathsWithCrostini",
@@ -325,7 +318,7 @@
 // Implements the chrome.fileManagerPrivate.unsharePathWithCrostini
 // method.  Unshares specified path.
 class FileManagerPrivateInternalUnsharePathWithCrostiniFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION(
       "fileManagerPrivateInternal.unsharePathWithCrostini",
@@ -346,7 +339,7 @@
 // Implements the chrome.fileManagerPrivate.getCrostiniSharedPaths
 // method.  Returns list of file entries.
 class FileManagerPrivateInternalGetCrostiniSharedPathsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION(
       "fileManagerPrivateInternal.getCrostiniSharedPaths",
@@ -366,7 +359,7 @@
 // Implements the chrome.fileManagerPrivate.getLinuxPackageInfo method.
 // Retrieves information about a Linux package.
 class FileManagerPrivateInternalGetLinuxPackageInfoFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.getLinuxPackageInfo",
                              FILEMANAGERPRIVATEINTERNAL_GETLINUXPACKAGEINFO)
@@ -386,7 +379,7 @@
 // Implements the chrome.fileManagerPrivate.installLinuxPackage method.
 // Starts installation of a Linux package.
 class FileManagerPrivateInternalInstallLinuxPackageFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.installLinuxPackage",
                              FILEMANAGERPRIVATEINTERNAL_INSTALLLINUXPACKAGE)
@@ -404,7 +397,7 @@
 
 // Implements the chrome.fileManagerPrivate.getCustomActions method.
 class FileManagerPrivateInternalGetCustomActionsFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalGetCustomActionsFunction();
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.getCustomActions",
@@ -423,7 +416,7 @@
 
 // Implements the chrome.fileManagerPrivate.executeCustomAction method.
 class FileManagerPrivateInternalExecuteCustomActionFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalExecuteCustomActionFunction();
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.executeCustomAction",
@@ -442,7 +435,7 @@
 
 // Implements the chrome.fileManagerPrivateInternal.getRecentFiles method.
 class FileManagerPrivateInternalGetRecentFilesFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalGetRecentFilesFunction();
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.getRecentFiles",
@@ -465,7 +458,7 @@
 
 // Implements the chrome.fileManagerPrivate.detectCharacterEncoding method.
 class FileManagerPrivateDetectCharacterEncodingFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.detectCharacterEncoding",
                              FILEMANAGERPRIVATE_DETECTCHARACTERENCODING)
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_mount.h b/chrome/browser/chromeos/extensions/file_manager/private_api_mount.h
index af49e745..348ebcd 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_mount.h
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_mount.h
@@ -19,8 +19,7 @@
 
 // Implements chrome.fileManagerPrivate.addMount method.
 // Mounts removable devices and archive files.
-class FileManagerPrivateAddMountFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateAddMountFunction : public LoggedExtensionFunction {
  public:
   FileManagerPrivateAddMountFunction();
 
@@ -58,8 +57,7 @@
 
 // Implements chrome.fileManagerPrivate.removeMount method.
 // Unmounts selected volume. Expects volume id as an argument.
-class FileManagerPrivateRemoveMountFunction
-    : public LoggedUIThreadExtensionFunction {
+class FileManagerPrivateRemoveMountFunction : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.removeMount",
                              FILEMANAGERPRIVATE_REMOVEMOUNT)
@@ -74,7 +72,7 @@
 // Implements chrome.fileManagerPrivate.markCacheAsMounted method.
 // Marks a cached file as mounted or unmounted.
 class FileManagerPrivateMarkCacheAsMountedFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateMarkCacheAsMountedFunction();
 
@@ -107,7 +105,7 @@
 
 // Implements chrome.fileManagerPrivate.getVolumeMetadataList method.
 class FileManagerPrivateGetVolumeMetadataListFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.getVolumeMetadataList",
                              FILEMANAGERPRIVATE_GETVOLUMEMETADATALIST)
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_strings.h b/chrome/browser/chromeos/extensions/file_manager/private_api_strings.h
index 95ebdbc..7d2d1f3 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_strings.h
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_strings.h
@@ -13,7 +13,7 @@
 
 // Implements the chrome.fileManagerPrivate.getStrings method.
 // Used to get strings for the file manager from JavaScript.
-class FileManagerPrivateGetStringsFunction : public UIThreadExtensionFunction {
+class FileManagerPrivateGetStringsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivate.getStrings",
                              FILEMANAGERPRIVATE_GETSTRINGS)
diff --git a/chrome/browser/chromeos/extensions/file_manager/private_api_tasks.h b/chrome/browser/chromeos/extensions/file_manager/private_api_tasks.h
index 1f9e8548..1127fec 100644
--- a/chrome/browser/chromeos/extensions/file_manager/private_api_tasks.h
+++ b/chrome/browser/chromeos/extensions/file_manager/private_api_tasks.h
@@ -29,7 +29,7 @@
 
 // Implements the chrome.fileManagerPrivateInternal.executeTask method.
 class FileManagerPrivateInternalExecuteTaskFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalExecuteTaskFunction();
 
@@ -39,7 +39,7 @@
  protected:
   ~FileManagerPrivateInternalExecuteTaskFunction() override = default;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
@@ -51,7 +51,7 @@
 
 // Implements the chrome.fileManagerPrivateInternal.getFileTasks method.
 class FileManagerPrivateInternalGetFileTasksFunction
-    : public LoggedUIThreadExtensionFunction {
+    : public LoggedExtensionFunction {
  public:
   FileManagerPrivateInternalGetFileTasksFunction();
 
@@ -61,7 +61,7 @@
  protected:
   ~FileManagerPrivateInternalGetFileTasksFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
@@ -87,7 +87,7 @@
 
 // Implements the chrome.fileManagerPrivateInternal.setDefaultTask method.
 class FileManagerPrivateInternalSetDefaultTaskFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileManagerPrivateInternal.setDefaultTask",
                              FILEMANAGERPRIVATEINTERNAL_SETDEFAULTTASK)
diff --git a/chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.h b/chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.h
index e5aab5e..4004b188 100644
--- a/chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.h
+++ b/chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.h
@@ -10,7 +10,7 @@
 
 namespace extensions {
 
-class FileSystemProviderMountFunction : public UIThreadExtensionFunction {
+class FileSystemProviderMountFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileSystemProvider.mount",
                              FILESYSTEMPROVIDER_MOUNT)
@@ -20,7 +20,7 @@
   ResponseAction Run() override;
 };
 
-class FileSystemProviderUnmountFunction : public UIThreadExtensionFunction {
+class FileSystemProviderUnmountFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileSystemProvider.unmount",
                              FILESYSTEMPROVIDER_UNMOUNT)
@@ -30,7 +30,7 @@
   ResponseAction Run() override;
 };
 
-class FileSystemProviderGetAllFunction : public UIThreadExtensionFunction {
+class FileSystemProviderGetAllFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileSystemProvider.getAll",
                              FILESYSTEMPROVIDER_GETALL)
@@ -40,7 +40,7 @@
   ResponseAction Run() override;
 };
 
-class FileSystemProviderGetFunction : public UIThreadExtensionFunction {
+class FileSystemProviderGetFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fileSystemProvider.get", FILESYSTEMPROVIDER_GET)
 
diff --git a/chrome/browser/chromeos/extensions/file_system_provider/provider_function.cc b/chrome/browser/chromeos/extensions/file_system_provider/provider_function.cc
index 868ca65..79402b41 100644
--- a/chrome/browser/chromeos/extensions/file_system_provider/provider_function.cc
+++ b/chrome/browser/chromeos/extensions/file_system_provider/provider_function.cc
@@ -148,7 +148,7 @@
 }
 
 bool FileSystemProviderInternalFunction::PreRunValidation(std::string* error) {
-  if (!UIThreadExtensionFunction::PreRunValidation(error))
+  if (!ExtensionFunction::PreRunValidation(error))
     return false;
 
   std::string file_system_id;
diff --git a/chrome/browser/chromeos/extensions/file_system_provider/provider_function.h b/chrome/browser/chromeos/extensions/file_system_provider/provider_function.h
index 14a542a..c7975d8 100644
--- a/chrome/browser/chromeos/extensions/file_system_provider/provider_function.h
+++ b/chrome/browser/chromeos/extensions/file_system_provider/provider_function.h
@@ -46,7 +46,7 @@
 
 // Base class for internal API functions handling request results, either
 // a success or a failure.
-class FileSystemProviderInternalFunction : public UIThreadExtensionFunction {
+class FileSystemProviderInternalFunction : public ExtensionFunction {
  public:
   FileSystemProviderInternalFunction();
 
diff --git a/chrome/browser/chromeos/extensions/info_private_api.h b/chrome/browser/chromeos/extensions/info_private_api.h
index 990dc86..6031439 100644
--- a/chrome/browser/chromeos/extensions/info_private_api.h
+++ b/chrome/browser/chromeos/extensions/info_private_api.h
@@ -16,14 +16,14 @@
 
 namespace extensions {
 
-class ChromeosInfoPrivateGetFunction : public UIThreadExtensionFunction {
+class ChromeosInfoPrivateGetFunction : public ExtensionFunction {
  public:
   ChromeosInfoPrivateGetFunction();
 
  protected:
   ~ChromeosInfoPrivateGetFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
@@ -33,21 +33,20 @@
   DECLARE_EXTENSION_FUNCTION("chromeosInfoPrivate.get", CHROMEOSINFOPRIVATE_GET)
 };
 
-class ChromeosInfoPrivateSetFunction : public UIThreadExtensionFunction {
+class ChromeosInfoPrivateSetFunction : public ExtensionFunction {
  public:
   ChromeosInfoPrivateSetFunction();
 
  protected:
   ~ChromeosInfoPrivateSetFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
   DECLARE_EXTENSION_FUNCTION("chromeosInfoPrivate.set", CHROMEOSINFOPRIVATE_SET)
 };
 
-
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_CHROMEOS_EXTENSIONS_INFO_PRIVATE_API_H_
diff --git a/chrome/browser/chromeos/extensions/input_method_api.h b/chrome/browser/chromeos/extensions/input_method_api.h
index ac44931..4aa05a3 100644
--- a/chrome/browser/chromeos/extensions/input_method_api.h
+++ b/chrome/browser/chromeos/extensions/input_method_api.h
@@ -24,7 +24,7 @@
 
 // Implements the inputMethodPrivate.getInputMethodConfig  method.
 class InputMethodPrivateGetInputMethodConfigFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   InputMethodPrivateGetInputMethodConfigFunction() {}
 
@@ -41,7 +41,7 @@
 
 // Implements the inputMethodPrivate.getCurrentInputMethod method.
 class InputMethodPrivateGetCurrentInputMethodFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   InputMethodPrivateGetCurrentInputMethodFunction() {}
 
@@ -58,7 +58,7 @@
 
 // Implements the inputMethodPrivate.setCurrentInputMethod method.
 class InputMethodPrivateSetCurrentInputMethodFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   InputMethodPrivateSetCurrentInputMethodFunction() {}
 
@@ -74,8 +74,7 @@
 };
 
 // Implements the inputMethodPrivate.getInputMethods method.
-class InputMethodPrivateGetInputMethodsFunction
-    : public UIThreadExtensionFunction {
+class InputMethodPrivateGetInputMethodsFunction : public ExtensionFunction {
  public:
   InputMethodPrivateGetInputMethodsFunction() {}
 
@@ -92,7 +91,7 @@
 
 // Implements the inputMethodPrivate.fetchAllDictionaryWords method.
 class InputMethodPrivateFetchAllDictionaryWordsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   InputMethodPrivateFetchAllDictionaryWordsFunction() {}
 
@@ -108,8 +107,7 @@
 };
 
 // Implements the inputMethodPrivate.addWordToDictionary method.
-class InputMethodPrivateAddWordToDictionaryFunction
-    : public UIThreadExtensionFunction {
+class InputMethodPrivateAddWordToDictionaryFunction : public ExtensionFunction {
  public:
   InputMethodPrivateAddWordToDictionaryFunction() {}
 
@@ -126,7 +124,7 @@
 
 // Implements the inputMethodPrivate.getEncryptSyncEnabled method.
 class InputMethodPrivateGetEncryptSyncEnabledFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   InputMethodPrivateGetEncryptSyncEnabledFunction() {}
 
@@ -142,8 +140,7 @@
 };
 
 // Implements the inputMethodPrivate.setXkbLayout method.
-class InputMethodPrivateSetXkbLayoutFunction
-    : public UIThreadExtensionFunction {
+class InputMethodPrivateSetXkbLayoutFunction : public ExtensionFunction {
  public:
   InputMethodPrivateSetXkbLayoutFunction() {}
 
@@ -159,8 +156,7 @@
 };
 
 // Implements the inputMethodPrivate.showInputView method.
-class InputMethodPrivateShowInputViewFunction
-    : public UIThreadExtensionFunction {
+class InputMethodPrivateShowInputViewFunction : public ExtensionFunction {
  public:
   InputMethodPrivateShowInputViewFunction() {}
 
@@ -176,8 +172,7 @@
 };
 
 // Implements the inputMethodPrivate.openOptionsPage method.
-class InputMethodPrivateOpenOptionsPageFunction
-    : public UIThreadExtensionFunction {
+class InputMethodPrivateOpenOptionsPageFunction : public ExtensionFunction {
  public:
   InputMethodPrivateOpenOptionsPageFunction() {}
 
@@ -192,8 +187,7 @@
   DISALLOW_COPY_AND_ASSIGN(InputMethodPrivateOpenOptionsPageFunction);
 };
 
-class InputMethodPrivateGetSurroundingTextFunction
-    : public UIThreadExtensionFunction {
+class InputMethodPrivateGetSurroundingTextFunction : public ExtensionFunction {
  public:
   InputMethodPrivateGetSurroundingTextFunction() {}
 
@@ -208,7 +202,7 @@
   DISALLOW_COPY_AND_ASSIGN(InputMethodPrivateGetSurroundingTextFunction);
 };
 
-class InputMethodPrivateGetSettingFunction : public UIThreadExtensionFunction {
+class InputMethodPrivateGetSettingFunction : public ExtensionFunction {
  public:
   InputMethodPrivateGetSettingFunction() = default;
 
@@ -224,7 +218,7 @@
   DISALLOW_COPY_AND_ASSIGN(InputMethodPrivateGetSettingFunction);
 };
 
-class InputMethodPrivateSetSettingFunction : public UIThreadExtensionFunction {
+class InputMethodPrivateSetSettingFunction : public ExtensionFunction {
  public:
   InputMethodPrivateSetSettingFunction() = default;
 
@@ -240,8 +234,7 @@
   DISALLOW_COPY_AND_ASSIGN(InputMethodPrivateSetSettingFunction);
 };
 
-class InputMethodPrivateSetCompositionRangeFunction
-    : public UIThreadExtensionFunction {
+class InputMethodPrivateSetCompositionRangeFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("inputMethodPrivate.setCompositionRange",
                              INPUTMETHODPRIVATE_SETCOMPOSITIONRANGE)
@@ -249,7 +242,7 @@
  protected:
   ~InputMethodPrivateSetCompositionRangeFunction() override {}
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 };
 
diff --git a/chrome/browser/chromeos/extensions/launcher_search_provider.h b/chrome/browser/chromeos/extensions/launcher_search_provider.h
index 741d5aab6..40f0d09 100644
--- a/chrome/browser/chromeos/extensions/launcher_search_provider.h
+++ b/chrome/browser/chromeos/extensions/launcher_search_provider.h
@@ -11,7 +11,7 @@
 
 // Implements chrome.launcherSearchProvider.setSearchResults method.
 class LauncherSearchProviderSetSearchResultsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("launcherSearchProvider.setSearchResults",
                              LAUNCHERSEARCHPROVIDER_SETSEARCHRESULTS)
diff --git a/chrome/browser/chromeos/extensions/login_screen/login/login_api.h b/chrome/browser/chromeos/extensions/login_screen/login/login_api.h
index 20ff168d..c0a65fd5 100644
--- a/chrome/browser/chromeos/extensions/login_screen/login/login_api.h
+++ b/chrome/browser/chromeos/extensions/login_screen/login/login_api.h
@@ -17,8 +17,7 @@
 
 }
 
-class LoginLaunchManagedGuestSessionFunction
-    : public UIThreadExtensionFunction {
+class LoginLaunchManagedGuestSessionFunction : public ExtensionFunction {
  public:
   LoginLaunchManagedGuestSessionFunction();
 
@@ -35,7 +34,7 @@
   DISALLOW_COPY_AND_ASSIGN(LoginLaunchManagedGuestSessionFunction);
 };
 
-class LoginExitCurrentSessionFunction : public UIThreadExtensionFunction {
+class LoginExitCurrentSessionFunction : public ExtensionFunction {
  public:
   LoginExitCurrentSessionFunction();
 
@@ -52,7 +51,7 @@
   DISALLOW_COPY_AND_ASSIGN(LoginExitCurrentSessionFunction);
 };
 
-class LoginIsRunningInLoginProfileFunction : public UIThreadExtensionFunction {
+class LoginIsRunningInLoginProfileFunction : public ExtensionFunction {
  public:
   LoginIsRunningInLoginProfileFunction();
 
@@ -69,8 +68,7 @@
   DISALLOW_COPY_AND_ASSIGN(LoginIsRunningInLoginProfileFunction);
 };
 
-class LoginFetchDataForNextLoginAttemptFunction
-    : public UIThreadExtensionFunction {
+class LoginFetchDataForNextLoginAttemptFunction : public ExtensionFunction {
  public:
   LoginFetchDataForNextLoginAttemptFunction();
 
diff --git a/chrome/browser/chromeos/extensions/login_screen/login_screen_ui/login_screen_ui_api.h b/chrome/browser/chromeos/extensions/login_screen/login_screen_ui/login_screen_ui_api.h
index 5c9f342..8d5f2cb2 100644
--- a/chrome/browser/chromeos/extensions/login_screen/login_screen_ui/login_screen_ui_api.h
+++ b/chrome/browser/chromeos/extensions/login_screen/login_screen_ui/login_screen_ui_api.h
@@ -9,7 +9,7 @@
 
 namespace extensions {
 
-class LoginScreenUiShowFunction : public UIThreadExtensionFunction {
+class LoginScreenUiShowFunction : public ExtensionFunction {
  public:
   LoginScreenUiShowFunction();
 
@@ -25,7 +25,7 @@
   DISALLOW_COPY_AND_ASSIGN(LoginScreenUiShowFunction);
 };
 
-class LoginScreenUiCloseFunction : public UIThreadExtensionFunction {
+class LoginScreenUiCloseFunction : public ExtensionFunction {
  public:
   LoginScreenUiCloseFunction();
 
diff --git a/chrome/browser/chromeos/extensions/quick_unlock_private/quick_unlock_private_api.h b/chrome/browser/chromeos/extensions/quick_unlock_private/quick_unlock_private_api.h
index 6df6964..a3e52426 100644
--- a/chrome/browser/chromeos/extensions/quick_unlock_private/quick_unlock_private_api.h
+++ b/chrome/browser/chromeos/extensions/quick_unlock_private/quick_unlock_private_api.h
@@ -22,7 +22,7 @@
 namespace extensions {
 
 class QuickUnlockPrivateGetAuthTokenFunction
-    : public UIThreadExtensionFunction,
+    : public ExtensionFunction,
       public chromeos::AuthStatusConsumer {
  public:
   using AuthenticatorAllocator =
@@ -67,7 +67,7 @@
 };
 
 class QuickUnlockPrivateSetLockScreenEnabledFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   QuickUnlockPrivateSetLockScreenEnabledFunction();
   DECLARE_EXTENSION_FUNCTION("quickUnlockPrivate.setLockScreenEnabled",
@@ -85,8 +85,7 @@
   DISALLOW_COPY_AND_ASSIGN(QuickUnlockPrivateSetLockScreenEnabledFunction);
 };
 
-class QuickUnlockPrivateGetAvailableModesFunction
-    : public UIThreadExtensionFunction {
+class QuickUnlockPrivateGetAvailableModesFunction : public ExtensionFunction {
  public:
   QuickUnlockPrivateGetAvailableModesFunction();
   DECLARE_EXTENSION_FUNCTION("quickUnlockPrivate.getAvailableModes",
@@ -104,8 +103,7 @@
   DISALLOW_COPY_AND_ASSIGN(QuickUnlockPrivateGetAvailableModesFunction);
 };
 
-class QuickUnlockPrivateGetActiveModesFunction
-    : public UIThreadExtensionFunction {
+class QuickUnlockPrivateGetActiveModesFunction : public ExtensionFunction {
  public:
   QuickUnlockPrivateGetActiveModesFunction();
   DECLARE_EXTENSION_FUNCTION("quickUnlockPrivate.getActiveModes",
@@ -126,8 +124,7 @@
   DISALLOW_COPY_AND_ASSIGN(QuickUnlockPrivateGetActiveModesFunction);
 };
 
-class QuickUnlockPrivateCheckCredentialFunction
-    : public UIThreadExtensionFunction {
+class QuickUnlockPrivateCheckCredentialFunction : public ExtensionFunction {
  public:
   QuickUnlockPrivateCheckCredentialFunction();
   DECLARE_EXTENSION_FUNCTION("quickUnlockPrivate.checkCredential",
@@ -144,7 +141,7 @@
 };
 
 class QuickUnlockPrivateGetCredentialRequirementsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   QuickUnlockPrivateGetCredentialRequirementsFunction();
   DECLARE_EXTENSION_FUNCTION("quickUnlockPrivate.getCredentialRequirements",
@@ -160,7 +157,7 @@
   DISALLOW_COPY_AND_ASSIGN(QuickUnlockPrivateGetCredentialRequirementsFunction);
 };
 
-class QuickUnlockPrivateSetModesFunction : public UIThreadExtensionFunction {
+class QuickUnlockPrivateSetModesFunction : public ExtensionFunction {
  public:
   using QuickUnlockMode =
       extensions::api::quick_unlock_private::QuickUnlockMode;
diff --git a/chrome/browser/chromeos/extensions/quick_unlock_private/quick_unlock_private_api_unittest.cc b/chrome/browser/chromeos/extensions/quick_unlock_private/quick_unlock_private_api_unittest.cc
index 9e90689..a9b6e5a 100644
--- a/chrome/browser/chromeos/extensions/quick_unlock_private/quick_unlock_private_api_unittest.cc
+++ b/chrome/browser/chromeos/extensions/quick_unlock_private/quick_unlock_private_api_unittest.cc
@@ -471,7 +471,7 @@
  private:
   // Runs the given |func| with the given |params|.
   std::unique_ptr<base::Value> RunFunction(
-      scoped_refptr<UIThreadExtensionFunction> func,
+      scoped_refptr<ExtensionFunction> func,
       std::unique_ptr<base::ListValue> params) {
     base::RunLoop().RunUntilIdle();
     std::unique_ptr<base::Value> result =
@@ -485,7 +485,7 @@
 
   // Runs |func| with |params|. Expects and returns an error result.
   std::string RunFunctionAndReturnError(
-      scoped_refptr<UIThreadExtensionFunction> func,
+      scoped_refptr<ExtensionFunction> func,
       std::unique_ptr<base::ListValue> params) {
     base::RunLoop().RunUntilIdle();
     std::unique_ptr<ExtensionFunctionDispatcher> dispatcher(
diff --git a/chrome/browser/chromeos/extensions/users_private/users_private_api.h b/chrome/browser/chromeos/extensions/users_private/users_private_api.h
index c38bf86..eedf258 100644
--- a/chrome/browser/chromeos/extensions/users_private/users_private_api.h
+++ b/chrome/browser/chromeos/extensions/users_private/users_private_api.h
@@ -15,8 +15,7 @@
 namespace extensions {
 
 // Implements the chrome.usersPrivate.getWhitelistedUsers method.
-class UsersPrivateGetWhitelistedUsersFunction
-    : public UIThreadExtensionFunction {
+class UsersPrivateGetWhitelistedUsersFunction : public ExtensionFunction {
  public:
   UsersPrivateGetWhitelistedUsersFunction();
   DECLARE_EXTENSION_FUNCTION("usersPrivate.getWhitelistedUsers",
@@ -35,8 +34,7 @@
 };
 
 // Implements the chrome.usersPrivate.addWhitelistedUser method.
-class UsersPrivateAddWhitelistedUserFunction
-    : public UIThreadExtensionFunction {
+class UsersPrivateAddWhitelistedUserFunction : public ExtensionFunction {
  public:
   UsersPrivateAddWhitelistedUserFunction();
   DECLARE_EXTENSION_FUNCTION("usersPrivate.addWhitelistedUser",
@@ -45,7 +43,7 @@
  protected:
   ~UsersPrivateAddWhitelistedUserFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
@@ -55,8 +53,7 @@
 };
 
 // Implements the chrome.usersPrivate.removeWhitelistedUser method.
-class UsersPrivateRemoveWhitelistedUserFunction
-    : public UIThreadExtensionFunction {
+class UsersPrivateRemoveWhitelistedUserFunction : public ExtensionFunction {
  public:
   UsersPrivateRemoveWhitelistedUserFunction();
   DECLARE_EXTENSION_FUNCTION("usersPrivate.removeWhitelistedUser",
@@ -75,8 +72,7 @@
 };
 
 // Implements the chrome.usersPrivate.isWhitelistManaged method.
-class UsersPrivateIsWhitelistManagedFunction
-    : public UIThreadExtensionFunction {
+class UsersPrivateIsWhitelistManagedFunction : public ExtensionFunction {
  public:
   UsersPrivateIsWhitelistManagedFunction();
   DECLARE_EXTENSION_FUNCTION("usersPrivate.isWhitelistManaged",
@@ -93,7 +89,7 @@
 };
 
 // Implements the chrome.usersPrivate.getCurrentUser method.
-class UsersPrivateGetCurrentUserFunction : public UIThreadExtensionFunction {
+class UsersPrivateGetCurrentUserFunction : public ExtensionFunction {
  public:
   UsersPrivateGetCurrentUserFunction();
   DECLARE_EXTENSION_FUNCTION("usersPrivate.getCurrentUser",
@@ -110,7 +106,7 @@
   DISALLOW_COPY_AND_ASSIGN(UsersPrivateGetCurrentUserFunction);
 };
 
-class UsersPrivateGetLoginStatusFunction : public UIThreadExtensionFunction {
+class UsersPrivateGetLoginStatusFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("usersPrivate.getLoginStatus",
                              USERSPRIVATE_GETLOGINSTATUS)
diff --git a/chrome/browser/chromeos/extensions/wallpaper_api.h b/chrome/browser/chromeos/extensions/wallpaper_api.h
index 8a4f75b..adfd7f9 100644
--- a/chrome/browser/chromeos/extensions/wallpaper_api.h
+++ b/chrome/browser/chromeos/extensions/wallpaper_api.h
@@ -30,7 +30,7 @@
  protected:
   ~WallpaperSetWallpaperFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
diff --git a/chrome/browser/chromeos/extensions/wallpaper_function_base.h b/chrome/browser/chromeos/extensions/wallpaper_function_base.h
index c739a9b..13b30d3 100644
--- a/chrome/browser/chromeos/extensions/wallpaper_function_base.h
+++ b/chrome/browser/chromeos/extensions/wallpaper_function_base.h
@@ -33,7 +33,7 @@
 
 // Wallpaper manager function base. It contains a image decoder to decode
 // wallpaper data.
-class WallpaperFunctionBase : public UIThreadExtensionFunction {
+class WallpaperFunctionBase : public ExtensionFunction {
  public:
   static const int kWallpaperThumbnailWidth;
   static const int kWallpaperThumbnailHeight;
diff --git a/chrome/browser/chromeos/extensions/wallpaper_private_api.h b/chrome/browser/chromeos/extensions/wallpaper_private_api.h
index e8cfe3c..8696c8f0e 100644
--- a/chrome/browser/chromeos/extensions/wallpaper_private_api.h
+++ b/chrome/browser/chromeos/extensions/wallpaper_private_api.h
@@ -26,7 +26,7 @@
 }  // namespace backdrop_wallpaper_handlers
 
 // Wallpaper manager strings.
-class WallpaperPrivateGetStringsFunction : public UIThreadExtensionFunction {
+class WallpaperPrivateGetStringsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.getStrings",
                              WALLPAPERPRIVATE_GETSTRINGS)
@@ -39,8 +39,7 @@
 };
 
 // Check if sync themes setting is enabled.
-class WallpaperPrivateGetSyncSettingFunction
-    : public UIThreadExtensionFunction {
+class WallpaperPrivateGetSyncSettingFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.getSyncSetting",
                              WALLPAPERPRIVATE_GETSYNCSETTING)
@@ -60,8 +59,7 @@
   int retry_number_ = 0;
 };
 
-class WallpaperPrivateSetWallpaperIfExistsFunction
-    : public UIThreadExtensionFunction {
+class WallpaperPrivateSetWallpaperIfExistsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.setWallpaperIfExists",
                              WALLPAPERPRIVATE_SETWALLPAPERIFEXISTS)
@@ -71,7 +69,7 @@
  protected:
   ~WallpaperPrivateSetWallpaperIfExistsFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
@@ -81,7 +79,7 @@
   DISALLOW_COPY_AND_ASSIGN(WallpaperPrivateSetWallpaperIfExistsFunction);
 };
 
-class WallpaperPrivateSetWallpaperFunction : public UIThreadExtensionFunction {
+class WallpaperPrivateSetWallpaperFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.setWallpaper",
                              WALLPAPERPRIVATE_SETWALLPAPER)
@@ -91,7 +89,7 @@
  protected:
   ~WallpaperPrivateSetWallpaperFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
@@ -101,8 +99,7 @@
   DISALLOW_COPY_AND_ASSIGN(WallpaperPrivateSetWallpaperFunction);
 };
 
-class WallpaperPrivateResetWallpaperFunction
-    : public UIThreadExtensionFunction {
+class WallpaperPrivateResetWallpaperFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.resetWallpaper",
                              WALLPAPERPRIVATE_RESETWALLPAPER)
@@ -112,7 +109,7 @@
  protected:
   ~WallpaperPrivateResetWallpaperFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 };
 
@@ -127,7 +124,7 @@
  protected:
   ~WallpaperPrivateSetCustomWallpaperFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
@@ -145,7 +142,7 @@
 };
 
 class WallpaperPrivateSetCustomWallpaperLayoutFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.setCustomWallpaperLayout",
                              WALLPAPERPRIVATE_SETCUSTOMWALLPAPERLAYOUT)
@@ -155,12 +152,12 @@
  protected:
   ~WallpaperPrivateSetCustomWallpaperLayoutFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 };
 
 class WallpaperPrivateMinimizeInactiveWindowsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.minimizeInactiveWindows",
                              WALLPAPERPRIVATE_MINIMIZEINACTIVEWINDOWS)
@@ -173,7 +170,7 @@
 };
 
 class WallpaperPrivateRestoreMinimizedWindowsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.restoreMinimizedWindows",
                              WALLPAPERPRIVATE_RESTOREMINIMIZEDWINDOWS)
@@ -185,7 +182,7 @@
   ResponseAction Run() override;
 };
 
-class WallpaperPrivateGetThumbnailFunction : public UIThreadExtensionFunction {
+class WallpaperPrivateGetThumbnailFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.getThumbnail",
                              WALLPAPERPRIVATE_GETTHUMBNAIL)
@@ -195,7 +192,7 @@
  protected:
   ~WallpaperPrivateGetThumbnailFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
@@ -214,7 +211,7 @@
   void Get(const base::FilePath& path);
 };
 
-class WallpaperPrivateSaveThumbnailFunction : public UIThreadExtensionFunction {
+class WallpaperPrivateSaveThumbnailFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.saveThumbnail",
                              WALLPAPERPRIVATE_SAVETHUMBNAIL)
@@ -224,7 +221,7 @@
  protected:
   ~WallpaperPrivateSaveThumbnailFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
@@ -239,7 +236,7 @@
 };
 
 class WallpaperPrivateGetOfflineWallpaperListFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.getOfflineWallpaperList",
                              WALLPAPERPRIVATE_GETOFFLINEWALLPAPERLIST)
@@ -248,7 +245,7 @@
  protected:
   ~WallpaperPrivateGetOfflineWallpaperListFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
  private:
@@ -260,8 +257,7 @@
 
 // The wallpaper UMA is recorded when a new wallpaper is set, either by the
 // built-in Wallpaper Picker App, or by a third party App.
-class WallpaperPrivateRecordWallpaperUMAFunction
-    : public UIThreadExtensionFunction {
+class WallpaperPrivateRecordWallpaperUMAFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.recordWallpaperUMA",
                              WALLPAPERPRIVATE_RECORDWALLPAPERUMA)
@@ -273,8 +269,7 @@
   ResponseAction Run() override;
 };
 
-class WallpaperPrivateGetCollectionsInfoFunction
-    : public UIThreadExtensionFunction {
+class WallpaperPrivateGetCollectionsInfoFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.getCollectionsInfo",
                              WALLPAPERPRIVATE_GETCOLLECTIONSINFO)
@@ -283,7 +278,7 @@
  protected:
   ~WallpaperPrivateGetCollectionsInfoFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
@@ -299,7 +294,7 @@
   DISALLOW_COPY_AND_ASSIGN(WallpaperPrivateGetCollectionsInfoFunction);
 };
 
-class WallpaperPrivateGetImagesInfoFunction : public UIThreadExtensionFunction {
+class WallpaperPrivateGetImagesInfoFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.getImagesInfo",
                              WALLPAPERPRIVATE_GETIMAGESINFO)
@@ -308,7 +303,7 @@
  protected:
   ~WallpaperPrivateGetImagesInfoFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
@@ -324,8 +319,7 @@
   DISALLOW_COPY_AND_ASSIGN(WallpaperPrivateGetImagesInfoFunction);
 };
 
-class WallpaperPrivateGetLocalImagePathsFunction
-    : public UIThreadExtensionFunction {
+class WallpaperPrivateGetLocalImagePathsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.getLocalImagePaths",
                              WALLPAPERPRIVATE_GETLOCALIMAGEPATHS)
@@ -334,7 +328,7 @@
  protected:
   ~WallpaperPrivateGetLocalImagePathsFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
@@ -344,8 +338,7 @@
   DISALLOW_COPY_AND_ASSIGN(WallpaperPrivateGetLocalImagePathsFunction);
 };
 
-class WallpaperPrivateGetLocalImageDataFunction
-    : public UIThreadExtensionFunction {
+class WallpaperPrivateGetLocalImageDataFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.getLocalImageData",
                              WALLPAPERPRIVATE_GETLOCALIMAGEDATA)
@@ -354,7 +347,7 @@
  protected:
   ~WallpaperPrivateGetLocalImageDataFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
@@ -366,7 +359,7 @@
 };
 
 class WallpaperPrivateConfirmPreviewWallpaperFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.confirmPreviewWallpaper",
                              WALLPAPERPRIVATE_CONFIRMPREVIEWWALLPAPER)
@@ -375,7 +368,7 @@
  protected:
   ~WallpaperPrivateConfirmPreviewWallpaperFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
@@ -383,7 +376,7 @@
 };
 
 class WallpaperPrivateCancelPreviewWallpaperFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.cancelPreviewWallpaper",
                              WALLPAPERPRIVATE_CANCELPREVIEWWALLPAPER)
@@ -392,7 +385,7 @@
  protected:
   ~WallpaperPrivateCancelPreviewWallpaperFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
@@ -409,7 +402,7 @@
  protected:
   ~WallpaperPrivateGetCurrentWallpaperThumbnailFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
@@ -420,8 +413,7 @@
       WallpaperPrivateGetCurrentWallpaperThumbnailFunction);
 };
 
-class WallpaperPrivateGetSurpriseMeImageFunction
-    : public UIThreadExtensionFunction {
+class WallpaperPrivateGetSurpriseMeImageFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("wallpaperPrivate.getSurpriseMeImage",
                              WALLPAPERPRIVATE_GETSURPRISEMEIMAGE)
@@ -430,7 +422,7 @@
  protected:
   ~WallpaperPrivateGetSurpriseMeImageFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
diff --git a/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.h b/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.h
index d900d64..afee1976 100644
--- a/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.h
+++ b/chrome/browser/extensions/api/activity_log_private/activity_log_private_api.h
@@ -82,8 +82,7 @@
 };
 
 // The implementation of activityLogPrivate.deleteActivities
-class ActivityLogPrivateDeleteActivitiesFunction
-    : public UIThreadExtensionFunction {
+class ActivityLogPrivateDeleteActivitiesFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("activityLogPrivate.deleteActivities",
                              ACTIVITYLOGPRIVATE_DELETEACTIVITIES)
@@ -97,7 +96,7 @@
 
 // The implementation of activityLogPrivate.deleteActivitiesByExtension
 class ActivityLogPrivateDeleteActivitiesByExtensionFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("activityLogPrivate.deleteActivitiesByExtension",
                              ACTIVITYLOGPRIVATE_DELETEACTIVITIESBYEXTENSION)
@@ -110,8 +109,7 @@
 };
 
 // The implementation of activityLogPrivate.deleteDatabase
-class ActivityLogPrivateDeleteDatabaseFunction
-    : public UIThreadExtensionFunction {
+class ActivityLogPrivateDeleteDatabaseFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("activityLogPrivate.deleteDatabase",
                              ACTIVITYLOGPRIVATE_DELETEDATABASE)
@@ -124,7 +122,7 @@
 };
 
 // The implementation of activityLogPrivate.deleteUrls
-class ActivityLogPrivateDeleteUrlsFunction : public UIThreadExtensionFunction {
+class ActivityLogPrivateDeleteUrlsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("activityLogPrivate.deleteUrls",
                              ACTIVITYLOGPRIVATE_DELETEURLS)
diff --git a/chrome/browser/extensions/api/autofill_private/autofill_private_api.h b/chrome/browser/extensions/api/autofill_private/autofill_private_api.h
index 20a4924..5b42cd4 100644
--- a/chrome/browser/extensions/api/autofill_private/autofill_private_api.h
+++ b/chrome/browser/extensions/api/autofill_private/autofill_private_api.h
@@ -13,7 +13,7 @@
 
 namespace extensions {
 
-class AutofillPrivateSaveAddressFunction : public UIThreadExtensionFunction {
+class AutofillPrivateSaveAddressFunction : public ExtensionFunction {
  public:
   AutofillPrivateSaveAddressFunction();
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.saveAddress",
@@ -31,7 +31,7 @@
   DISALLOW_COPY_AND_ASSIGN(AutofillPrivateSaveAddressFunction);
 };
 
-class AutofillPrivateGetCountryListFunction : public UIThreadExtensionFunction {
+class AutofillPrivateGetCountryListFunction : public ExtensionFunction {
  public:
   AutofillPrivateGetCountryListFunction();
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.getCountryList",
@@ -49,8 +49,7 @@
   DISALLOW_COPY_AND_ASSIGN(AutofillPrivateGetCountryListFunction);
 };
 
-class AutofillPrivateGetAddressComponentsFunction :
-    public UIThreadExtensionFunction {
+class AutofillPrivateGetAddressComponentsFunction : public ExtensionFunction {
  public:
   AutofillPrivateGetAddressComponentsFunction() {}
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.getAddressComponents",
@@ -66,7 +65,7 @@
   DISALLOW_COPY_AND_ASSIGN(AutofillPrivateGetAddressComponentsFunction);
 };
 
-class AutofillPrivateGetAddressListFunction : public UIThreadExtensionFunction {
+class AutofillPrivateGetAddressListFunction : public ExtensionFunction {
  public:
   AutofillPrivateGetAddressListFunction();
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.getAddressList",
@@ -84,7 +83,7 @@
   DISALLOW_COPY_AND_ASSIGN(AutofillPrivateGetAddressListFunction);
 };
 
-class AutofillPrivateSaveCreditCardFunction : public UIThreadExtensionFunction {
+class AutofillPrivateSaveCreditCardFunction : public ExtensionFunction {
  public:
   AutofillPrivateSaveCreditCardFunction();
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.saveCreditCard",
@@ -102,7 +101,7 @@
   DISALLOW_COPY_AND_ASSIGN(AutofillPrivateSaveCreditCardFunction);
 };
 
-class AutofillPrivateRemoveEntryFunction : public UIThreadExtensionFunction {
+class AutofillPrivateRemoveEntryFunction : public ExtensionFunction {
  public:
   AutofillPrivateRemoveEntryFunction();
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.removeEntry",
@@ -120,8 +119,7 @@
   DISALLOW_COPY_AND_ASSIGN(AutofillPrivateRemoveEntryFunction);
 };
 
-class AutofillPrivateValidatePhoneNumbersFunction :
-    public UIThreadExtensionFunction {
+class AutofillPrivateValidatePhoneNumbersFunction : public ExtensionFunction {
  public:
   AutofillPrivateValidatePhoneNumbersFunction() {}
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.validatePhoneNumbers",
@@ -137,7 +135,7 @@
   DISALLOW_COPY_AND_ASSIGN(AutofillPrivateValidatePhoneNumbersFunction);
 };
 
-class AutofillPrivateMaskCreditCardFunction : public UIThreadExtensionFunction {
+class AutofillPrivateMaskCreditCardFunction : public ExtensionFunction {
  public:
   AutofillPrivateMaskCreditCardFunction();
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.maskCreditCard",
@@ -155,8 +153,7 @@
   DISALLOW_COPY_AND_ASSIGN(AutofillPrivateMaskCreditCardFunction);
 };
 
-class AutofillPrivateGetCreditCardListFunction
-    : public UIThreadExtensionFunction {
+class AutofillPrivateGetCreditCardListFunction : public ExtensionFunction {
  public:
   AutofillPrivateGetCreditCardListFunction();
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.getCreditCardList",
@@ -174,8 +171,7 @@
   DISALLOW_COPY_AND_ASSIGN(AutofillPrivateGetCreditCardListFunction);
 };
 
-class AutofillPrivateMigrateCreditCardsFunction
-    : public UIThreadExtensionFunction {
+class AutofillPrivateMigrateCreditCardsFunction : public ExtensionFunction {
  public:
   AutofillPrivateMigrateCreditCardsFunction();
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.migrateCreditCards",
@@ -194,7 +190,7 @@
 };
 
 class AutofillPrivateLogServerCardLinkClickedFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   AutofillPrivateLogServerCardLinkClickedFunction();
   DECLARE_EXTENSION_FUNCTION("autofillPrivate.logServerCardLinkClicked",
diff --git a/chrome/browser/extensions/api/automation_internal/chrome_automation_internal_api_delegate.cc b/chrome/browser/extensions/api/automation_internal/chrome_automation_internal_api_delegate.cc
index ea3db0a..f233313 100644
--- a/chrome/browser/extensions/api/automation_internal/chrome_automation_internal_api_delegate.cc
+++ b/chrome/browser/extensions/api/automation_internal/chrome_automation_internal_api_delegate.cc
@@ -66,7 +66,7 @@
 }
 
 content::WebContents* ChromeAutomationInternalApiDelegate::GetActiveWebContents(
-    UIThreadExtensionFunction* function) {
+    ExtensionFunction* function) {
   return ChromeExtensionFunctionDetails(function)
       .GetCurrentBrowser()
       ->tab_strip_model()
diff --git a/chrome/browser/extensions/api/automation_internal/chrome_automation_internal_api_delegate.h b/chrome/browser/extensions/api/automation_internal/chrome_automation_internal_api_delegate.h
index 474b575d..f2bdc73 100644
--- a/chrome/browser/extensions/api/automation_internal/chrome_automation_internal_api_delegate.h
+++ b/chrome/browser/extensions/api/automation_internal/chrome_automation_internal_api_delegate.h
@@ -26,7 +26,7 @@
                   std::string* error_msg) override;
   int GetTabId(content::WebContents* contents) override;
   content::WebContents* GetActiveWebContents(
-      UIThreadExtensionFunction* function) override;
+      ExtensionFunction* function) override;
   void EnableDesktop() override;
   ui::AXTreeID GetAXTreeID() override;
   void SetEventBundleSink(ui::AXEventBundleSink* sink) override;
diff --git a/chrome/browser/extensions/api/braille_display_private/braille_display_private_api.h b/chrome/browser/extensions/api/braille_display_private/braille_display_private_api.h
index d6a88e0..2684e50 100644
--- a/chrome/browser/extensions/api/braille_display_private/braille_display_private_api.h
+++ b/chrome/browser/extensions/api/braille_display_private/braille_display_private_api.h
@@ -107,7 +107,7 @@
 };
 
 class BrailleDisplayPrivateUpdateBluetoothBrailleDisplayAddressFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
   ~BrailleDisplayPrivateUpdateBluetoothBrailleDisplayAddressFunction()
       override {}
   ResponseAction Run() override;
diff --git a/chrome/browser/extensions/api/browsing_data/browsing_data_api.h b/chrome/browser/extensions/api/browsing_data/browsing_data_api.h
index d5a9a0c..2a588cf 100644
--- a/chrome/browser/extensions/api/browsing_data/browsing_data_api.h
+++ b/chrome/browser/extensions/api/browsing_data/browsing_data_api.h
@@ -61,7 +61,7 @@
 
 }  // namespace extension_browsing_data_api_constants
 
-class BrowsingDataSettingsFunction : public UIThreadExtensionFunction {
+class BrowsingDataSettingsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("browsingData.settings", BROWSINGDATA_SETTINGS)
 
diff --git a/chrome/browser/extensions/api/certificate_provider/certificate_provider_api.h b/chrome/browser/extensions/api/certificate_provider/certificate_provider_api.h
index 67b8ee0..b61e947 100644
--- a/chrome/browser/extensions/api/certificate_provider/certificate_provider_api.h
+++ b/chrome/browser/extensions/api/certificate_provider/certificate_provider_api.h
@@ -28,9 +28,9 @@
 }
 
 class CertificateProviderInternalReportCertificatesFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  private:
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ~CertificateProviderInternalReportCertificatesFunction() override;
   ResponseAction Run() override;
 
@@ -43,9 +43,9 @@
 };
 
 class CertificateProviderInternalReportSignatureFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  private:
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ~CertificateProviderInternalReportSignatureFunction() override;
   ResponseAction Run() override;
 
@@ -53,9 +53,9 @@
                              CERTIFICATEPROVIDERINTERNAL_REPORTSIGNATURE)
 };
 
-class CertificateProviderRequestPinFunction : public UIThreadExtensionFunction {
+class CertificateProviderRequestPinFunction : public ExtensionFunction {
  private:
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ~CertificateProviderRequestPinFunction() override;
   ResponseAction Run() override;
   bool ShouldSkipQuotaLimiting() const override;
@@ -68,10 +68,9 @@
                              CERTIFICATEPROVIDER_REQUESTPIN)
 };
 
-class CertificateProviderStopPinRequestFunction
-    : public UIThreadExtensionFunction {
+class CertificateProviderStopPinRequestFunction : public ExtensionFunction {
  private:
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ~CertificateProviderStopPinRequestFunction() override;
   ResponseAction Run() override;
 
diff --git a/chrome/browser/extensions/api/cloud_print_private/cloud_print_private_api.h b/chrome/browser/extensions/api/cloud_print_private/cloud_print_private_api.h
index eb7494ec..35900ac 100644
--- a/chrome/browser/extensions/api/cloud_print_private/cloud_print_private_api.h
+++ b/chrome/browser/extensions/api/cloud_print_private/cloud_print_private_api.h
@@ -48,8 +48,7 @@
   virtual std::vector<std::string> GetPrinters() = 0;
 };
 
-class CloudPrintPrivateSetupConnectorFunction
-    : public UIThreadExtensionFunction {
+class CloudPrintPrivateSetupConnectorFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("cloudPrintPrivate.setupConnector",
                              CLOUDPRINTPRIVATE_SETUPCONNECTOR)
@@ -63,7 +62,7 @@
   ResponseAction Run() override;
 };
 
-class CloudPrintPrivateGetHostNameFunction : public UIThreadExtensionFunction {
+class CloudPrintPrivateGetHostNameFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("cloudPrintPrivate.getHostName",
                              CLOUDPRINTPRIVATE_GETHOSTNAME)
@@ -77,7 +76,7 @@
   ResponseAction Run() override;
 };
 
-class CloudPrintPrivateGetPrintersFunction : public UIThreadExtensionFunction {
+class CloudPrintPrivateGetPrintersFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("cloudPrintPrivate.getPrinters",
                              CLOUDPRINTPRIVATE_GETPRINTERS)
@@ -94,7 +93,7 @@
   ResponseAction Run() override;
 };
 
-class CloudPrintPrivateGetClientIdFunction : public UIThreadExtensionFunction {
+class CloudPrintPrivateGetClientIdFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("cloudPrintPrivate.getClientId",
                              CLOUDPRINTPRIVATE_GETCLIENTID)
diff --git a/chrome/browser/extensions/api/command_line_private/command_line_private_api.h b/chrome/browser/extensions/api/command_line_private/command_line_private_api.h
index 4ab0dd1..56841a47 100644
--- a/chrome/browser/extensions/api/command_line_private/command_line_private_api.h
+++ b/chrome/browser/extensions/api/command_line_private/command_line_private_api.h
@@ -9,7 +9,7 @@
 
 namespace extensions {
 
-class CommandLinePrivateHasSwitchFunction : public UIThreadExtensionFunction {
+class CommandLinePrivateHasSwitchFunction : public ExtensionFunction {
   DECLARE_EXTENSION_FUNCTION("commandLinePrivate.hasSwitch",
                              COMMANDLINEPRIVATE_HASSWITCH)
  protected:
diff --git a/chrome/browser/extensions/api/commands/commands.h b/chrome/browser/extensions/api/commands/commands.h
index 16b940f..433bdd1 100644
--- a/chrome/browser/extensions/api/commands/commands.h
+++ b/chrome/browser/extensions/api/commands/commands.h
@@ -7,7 +7,7 @@
 
 #include "extensions/browser/extension_function.h"
 
-class GetAllCommandsFunction : public UIThreadExtensionFunction {
+class GetAllCommandsFunction : public ExtensionFunction {
   ~GetAllCommandsFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("commands.getAll", COMMANDS_GETALL)
diff --git a/chrome/browser/extensions/api/content_settings/content_settings_api.h b/chrome/browser/extensions/api/content_settings/content_settings_api.h
index fa0fb0c..be5d320 100644
--- a/chrome/browser/extensions/api/content_settings/content_settings_api.h
+++ b/chrome/browser/extensions/api/content_settings/content_settings_api.h
@@ -14,8 +14,7 @@
 
 namespace extensions {
 
-class ContentSettingsContentSettingClearFunction
-    : public UIThreadExtensionFunction {
+class ContentSettingsContentSettingClearFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("contentSettings.clear", CONTENTSETTINGS_CLEAR)
 
@@ -26,8 +25,7 @@
   ResponseAction Run() override;
 };
 
-class ContentSettingsContentSettingGetFunction
-    : public UIThreadExtensionFunction {
+class ContentSettingsContentSettingGetFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("contentSettings.get", CONTENTSETTINGS_GET)
 
@@ -38,8 +36,7 @@
   ResponseAction Run() override;
 };
 
-class ContentSettingsContentSettingSetFunction
-    : public UIThreadExtensionFunction {
+class ContentSettingsContentSettingSetFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("contentSettings.set", CONTENTSETTINGS_SET)
 
diff --git a/chrome/browser/extensions/api/context_menus/context_menus_api.h b/chrome/browser/extensions/api/context_menus/context_menus_api.h
index 78e00b7..4dc9f201 100644
--- a/chrome/browser/extensions/api/context_menus/context_menus_api.h
+++ b/chrome/browser/extensions/api/context_menus/context_menus_api.h
@@ -9,7 +9,7 @@
 
 namespace extensions {
 
-class ContextMenusCreateFunction : public UIThreadExtensionFunction {
+class ContextMenusCreateFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("contextMenus.create", CONTEXTMENUS_CREATE)
 
@@ -20,7 +20,7 @@
   ResponseAction Run() override;
 };
 
-class ContextMenusUpdateFunction : public UIThreadExtensionFunction {
+class ContextMenusUpdateFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("contextMenus.update", CONTEXTMENUS_UPDATE)
 
@@ -31,7 +31,7 @@
   ResponseAction Run() override;
 };
 
-class ContextMenusRemoveFunction : public UIThreadExtensionFunction {
+class ContextMenusRemoveFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("contextMenus.remove", CONTEXTMENUS_REMOVE)
 
@@ -42,7 +42,7 @@
   ResponseAction Run() override;
 };
 
-class ContextMenusRemoveAllFunction : public UIThreadExtensionFunction {
+class ContextMenusRemoveAllFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("contextMenus.removeAll", CONTEXTMENUS_REMOVEALL)
 
diff --git a/chrome/browser/extensions/api/cookies/cookies_api.h b/chrome/browser/extensions/api/cookies/cookies_api.h
index fbd37d6..1ac9de5 100644
--- a/chrome/browser/extensions/api/cookies/cookies_api.h
+++ b/chrome/browser/extensions/api/cookies/cookies_api.h
@@ -91,7 +91,7 @@
 };
 
 // Implements the cookies.get() extension function.
-class CookiesGetFunction : public UIThreadExtensionFunction {
+class CookiesGetFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("cookies.get", COOKIES_GET)
 
@@ -113,7 +113,7 @@
 };
 
 // Implements the cookies.getAll() extension function.
-class CookiesGetAllFunction : public UIThreadExtensionFunction {
+class CookiesGetAllFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("cookies.getAll", COOKIES_GETALL)
 
@@ -135,7 +135,7 @@
 };
 
 // Implements the cookies.set() extension function.
-class CookiesSetFunction : public UIThreadExtensionFunction {
+class CookiesSetFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("cookies.set", COOKIES_SET)
 
@@ -159,7 +159,7 @@
 };
 
 // Implements the cookies.remove() extension function.
-class CookiesRemoveFunction : public UIThreadExtensionFunction {
+class CookiesRemoveFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("cookies.remove", COOKIES_REMOVE)
 
@@ -180,7 +180,7 @@
 };
 
 // Implements the cookies.getAllCookieStores() extension function.
-class CookiesGetAllCookieStoresFunction : public UIThreadExtensionFunction {
+class CookiesGetAllCookieStoresFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("cookies.getAllCookieStores",
                              COOKIES_GETALLCOOKIESTORES)
diff --git a/chrome/browser/extensions/api/cryptotoken_private/cryptotoken_private_api.h b/chrome/browser/extensions/api/cryptotoken_private/cryptotoken_private_api.h
index 7c92493..9ac938c8 100644
--- a/chrome/browser/extensions/api/cryptotoken_private/cryptotoken_private_api.h
+++ b/chrome/browser/extensions/api/cryptotoken_private/cryptotoken_private_api.h
@@ -27,18 +27,18 @@
     user_prefs::PrefRegistrySyncable* registry);
 
 class CryptotokenPrivateCanOriginAssertAppIdFunction
-    : public UIThreadExtensionFunction {
-  public:
-    CryptotokenPrivateCanOriginAssertAppIdFunction();
-    DECLARE_EXTENSION_FUNCTION("cryptotokenPrivate.canOriginAssertAppId",
-                               CRYPTOTOKENPRIVATE_CANORIGINASSERTAPPID)
-  protected:
-    ~CryptotokenPrivateCanOriginAssertAppIdFunction() override {}
-    ResponseAction Run() override;
+    : public ExtensionFunction {
+ public:
+  CryptotokenPrivateCanOriginAssertAppIdFunction();
+  DECLARE_EXTENSION_FUNCTION("cryptotokenPrivate.canOriginAssertAppId",
+                             CRYPTOTOKENPRIVATE_CANORIGINASSERTAPPID)
+ protected:
+  ~CryptotokenPrivateCanOriginAssertAppIdFunction() override {}
+  ResponseAction Run() override;
 };
 
 class CryptotokenPrivateIsAppIdHashInEnterpriseContextFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   CryptotokenPrivateIsAppIdHashInEnterpriseContextFunction();
   DECLARE_EXTENSION_FUNCTION(
@@ -51,7 +51,7 @@
 };
 
 class CryptotokenPrivateCanAppIdGetAttestationFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   CryptotokenPrivateCanAppIdGetAttestationFunction();
   DECLARE_EXTENSION_FUNCTION("cryptotokenPrivate.canAppIdGetAttestation",
diff --git a/chrome/browser/extensions/api/cryptotoken_private/cryptotoken_private_api_unittest.cc b/chrome/browser/extensions/api/cryptotoken_private/cryptotoken_private_api_unittest.cc
index 0500f7e..4ed224a 100644
--- a/chrome/browser/extensions/api/cryptotoken_private/cryptotoken_private_api_unittest.cc
+++ b/chrome/browser/extensions/api/cryptotoken_private/cryptotoken_private_api_unittest.cc
@@ -31,7 +31,7 @@
 
 using namespace api::cryptotoken_private;
 
-bool GetSingleBooleanResult(UIThreadExtensionFunction* function, bool* result) {
+bool GetSingleBooleanResult(ExtensionFunction* function, bool* result) {
   const base::ListValue* result_list = function->GetResultList();
   if (!result_list) {
     ADD_FAILURE() << "Function has no result list.";
diff --git a/chrome/browser/extensions/api/dashboard_private/dashboard_private_api.h b/chrome/browser/extensions/api/dashboard_private/dashboard_private_api.h
index 66697ef..93a75ad 100644
--- a/chrome/browser/extensions/api/dashboard_private/dashboard_private_api.h
+++ b/chrome/browser/extensions/api/dashboard_private/dashboard_private_api.h
@@ -23,7 +23,7 @@
 class Extension;
 
 class DashboardPrivateShowPermissionPromptForDelegatedInstallFunction
-    : public UIThreadExtensionFunction,
+    : public ExtensionFunction,
       public WebstoreInstallHelper::Delegate {
  public:
   DECLARE_EXTENSION_FUNCTION(
diff --git a/chrome/browser/extensions/api/data_reduction_proxy/data_reduction_proxy_api.h b/chrome/browser/extensions/api/data_reduction_proxy/data_reduction_proxy_api.h
index 8af53d7..0730691 100644
--- a/chrome/browser/extensions/api/data_reduction_proxy/data_reduction_proxy_api.h
+++ b/chrome/browser/extensions/api/data_reduction_proxy/data_reduction_proxy_api.h
@@ -15,8 +15,7 @@
 
 namespace extensions {
 
-class DataReductionProxyClearDataSavingsFunction
-    : public UIThreadExtensionFunction {
+class DataReductionProxyClearDataSavingsFunction : public ExtensionFunction {
  private:
   ~DataReductionProxyClearDataSavingsFunction() override {}
 
@@ -26,8 +25,7 @@
   ResponseAction Run() override;
 };
 
-class DataReductionProxyGetDataUsageFunction
-    : public UIThreadExtensionFunction {
+class DataReductionProxyGetDataUsageFunction : public ExtensionFunction {
  private:
   ~DataReductionProxyGetDataUsageFunction() override {}
 
diff --git a/chrome/browser/extensions/api/desktop_capture/desktop_capture_base.h b/chrome/browser/extensions/api/desktop_capture/desktop_capture_base.h
index 595a331..798348f 100644
--- a/chrome/browser/extensions/api/desktop_capture/desktop_capture_base.h
+++ b/chrome/browser/extensions/api/desktop_capture/desktop_capture_base.h
@@ -67,7 +67,7 @@
 };
 
 class DesktopCaptureCancelChooseDesktopMediaFunctionBase
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DesktopCaptureCancelChooseDesktopMediaFunctionBase();
 
diff --git a/chrome/browser/extensions/api/developer_private/developer_private_api.h b/chrome/browser/extensions/api/developer_private/developer_private_api.h
index 4113d20..639cf9e 100644
--- a/chrome/browser/extensions/api/developer_private/developer_private_api.h
+++ b/chrome/browser/extensions/api/developer_private/developer_private_api.h
@@ -294,7 +294,7 @@
 
 namespace api {
 
-class DeveloperPrivateAPIFunction : public UIThreadExtensionFunction {
+class DeveloperPrivateAPIFunction : public ExtensionFunction {
  protected:
   ~DeveloperPrivateAPIFunction() override;
 
@@ -488,7 +488,7 @@
   DISALLOW_COPY_AND_ASSIGN(DeveloperPrivateShowPermissionsDialogFunction);
 };
 
-class DeveloperPrivateChooseEntryFunction : public UIThreadExtensionFunction,
+class DeveloperPrivateChooseEntryFunction : public ExtensionFunction,
                                             public EntryPickerClient {
  protected:
   ~DeveloperPrivateChooseEntryFunction() override;
@@ -498,7 +498,6 @@
                   int file_type_index);
 };
 
-
 class DeveloperPrivateLoadUnpackedFunction
     : public DeveloperPrivateChooseEntryFunction {
  public:
@@ -611,8 +610,7 @@
   std::string key_path_str_;
 };
 
-class DeveloperPrivateIsProfileManagedFunction
-    : public UIThreadExtensionFunction {
+class DeveloperPrivateIsProfileManagedFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("developerPrivate.isProfileManaged",
                              DEVELOPERPRIVATE_ISPROFILEMANAGED)
diff --git a/chrome/browser/extensions/api/developer_private/developer_private_api_unittest.cc b/chrome/browser/extensions/api/developer_private/developer_private_api_unittest.cc
index d4de3f8..91bb48ea2 100644
--- a/chrome/browser/extensions/api/developer_private/developer_private_api_unittest.cc
+++ b/chrome/browser/extensions/api/developer_private/developer_private_api_unittest.cc
@@ -126,7 +126,7 @@
 
   // A wrapper around extension_function_test_utils::RunFunction that runs with
   // the associated browser, no flags, and can take stack-allocated arguments.
-  bool RunFunction(const scoped_refptr<UIThreadExtensionFunction>& function,
+  bool RunFunction(const scoped_refptr<ExtensionFunction>& function,
                    const base::ListValue& args);
 
   // Loads an unpacked extension that is backed by a real directory, allowing
@@ -184,7 +184,7 @@
 };
 
 bool DeveloperPrivateApiUnitTest::RunFunction(
-    const scoped_refptr<UIThreadExtensionFunction>& function,
+    const scoped_refptr<ExtensionFunction>& function,
     const base::ListValue& args) {
   return extension_function_test_utils::RunFunction(
       function.get(), args.CreateDeepCopy(), browser(), api_test_utils::NONE);
@@ -234,7 +234,7 @@
     const base::Callback<bool()>& has_pref,
     const std::string& key,
     const std::string& extension_id) {
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivateUpdateExtensionConfigurationFunction());
 
   EXPECT_FALSE(has_pref.Run()) << key;
@@ -279,7 +279,7 @@
     const base::ListValue& args,
     api::developer_private::PackStatus expected_status,
     int expected_flags) {
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivatePackDirectoryFunction());
   if (!RunFunction(function, args))
     return testing::AssertionFailure() << "Could not run function.";
@@ -308,7 +308,7 @@
 
 void DeveloperPrivateApiUnitTest::UpdateProfileConfigurationDevMode(
     bool dev_mode) {
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivateUpdateProfileConfigurationFunction());
   std::unique_ptr<base::ListValue> args =
       ListBuilder()
@@ -319,7 +319,7 @@
 
 void DeveloperPrivateApiUnitTest::GetProfileConfiguration(
     std::unique_ptr<api::developer_private::ProfileInfo>* profile_info) {
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivateGetProfileConfigurationFunction());
   base::ListValue args;
   EXPECT_TRUE(RunFunction(function, args)) << function->GetError();
@@ -337,7 +337,7 @@
     base::StringPiece new_access) {
   SCOPED_TRACE(new_access);
   ExtensionFunction::ScopedUserGestureForTests scoped_user_gesture;
-  scoped_refptr<UIThreadExtensionFunction> function = base::MakeRefCounted<
+  scoped_refptr<ExtensionFunction> function = base::MakeRefCounted<
       api::DeveloperPrivateUpdateExtensionConfigurationFunction>();
   std::string args =
       base::StringPrintf(R"([{"extensionId": "%s", "hostAccess": "%s"}])",
@@ -405,7 +405,7 @@
 TEST_F(DeveloperPrivateApiUnitTest, DeveloperPrivateReload) {
   const Extension* extension = LoadUnpackedExtension();
   std::string extension_id = extension->id();
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivateReloadFunction());
   base::ListValue reload_args;
   reload_args.AppendString(extension_id);
@@ -486,7 +486,7 @@
   base::ListValue choose_args;
   choose_args.AppendString("FOLDER");
   choose_args.AppendString("LOAD");
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivateChoosePathFunction());
   function->SetRenderFrameHost(web_contents->GetMainFrame());
   EXPECT_TRUE(RunFunction(function, choose_args)) << function->GetError();
@@ -527,7 +527,7 @@
 
   // Try loading a good extension (it should succeed, and the extension should
   // be added).
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivateLoadUnpackedFunction());
   function->SetRenderFrameHost(web_contents->GetMainFrame());
   ExtensionIdSet current_ids = registry()->enabled_extensions().GetIDs();
@@ -577,7 +577,7 @@
     base::FilePath path = dir.UnpackedPath();
     api::EntryPicker::SkipPickerAndAlwaysSelectPathForTest(&path);
 
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new api::DeveloperPrivateLoadUnpackedFunction());
     function->SetRenderFrameHost(web_contents->GetMainFrame());
     std::unique_ptr<base::Value> result =
@@ -604,7 +604,7 @@
     base::FilePath path = dir.UnpackedPath();
     api::EntryPicker::SkipPickerAndAlwaysSelectPathForTest(&path);
 
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new api::DeveloperPrivateLoadUnpackedFunction());
     function->SetRenderFrameHost(web_contents->GetMainFrame());
     std::unique_ptr<base::Value> result =
@@ -636,7 +636,7 @@
     base::FilePath path = dir.UnpackedPath();
     api::EntryPicker::SkipPickerAndAlwaysSelectPathForTest(&path);
 
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new api::DeveloperPrivateLoadUnpackedFunction());
     function->SetRenderFrameHost(web_contents->GetMainFrame());
     std::unique_ptr<base::Value> result =
@@ -669,7 +669,7 @@
   {
     // Trying to load the extension should result in a load error with the
     // retry id populated.
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new api::DeveloperPrivateLoadUnpackedFunction());
     function->SetRenderFrameHost(web_contents->GetMainFrame());
     std::unique_ptr<base::Value> result =
@@ -689,7 +689,7 @@
     // same retry id.  This is somewhat an implementation detail, but is
     // important to ensure we don't allocate crazy numbers of ids if the user
     // just retries continuously.
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new api::DeveloperPrivateLoadUnpackedFunction());
     function->SetRenderFrameHost(web_contents->GetMainFrame());
     std::unique_ptr<base::Value> result =
@@ -718,7 +718,7 @@
     base::FilePath second_path = second_dir.UnpackedPath();
     api::EntryPicker::SkipPickerAndAlwaysSelectPathForTest(&second_path);
 
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new api::DeveloperPrivateLoadUnpackedFunction());
     function->SetRenderFrameHost(web_contents->GetMainFrame());
     std::unique_ptr<base::Value> result =
@@ -749,7 +749,7 @@
 
   {
     // Try reloading the extension by supplying the retry id. It should succeed.
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new api::DeveloperPrivateLoadUnpackedFunction());
     function->SetRenderFrameHost(web_contents->GetMainFrame());
     TestExtensionRegistryObserver observer(registry());
@@ -766,7 +766,7 @@
 
   {
     // Try supplying an invalid retry id. It should fail with an error.
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new api::DeveloperPrivateLoadUnpackedFunction());
     function->SetRenderFrameHost(web_contents->GetMainFrame());
     std::string error = api_test_utils::RunFunctionAndReturnError(
@@ -995,7 +995,7 @@
   properties.message = kErrorMessage;
   properties.manifest_key.reset(new std::string("name"));
 
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivateRequestFileSourceFunction());
   base::ListValue file_source_args;
   file_source_args.Append(properties.ToValue());
@@ -1021,7 +1021,7 @@
   // ExtensionInfoGenerator's unittest), but rather just to make sure we can
   // serialize/deserialize the result - which implicity tests that everything
   // has a sane value.
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivateGetExtensionsInfoFunction());
   EXPECT_TRUE(RunFunction(function, base::ListValue())) << function->GetError();
   const base::ListValue* results = function->GetResultList();
@@ -1080,7 +1080,7 @@
                       .Set("type", type_string)
                       .Build())
           .Build();
-  scoped_refptr<UIThreadExtensionFunction> function =
+  scoped_refptr<ExtensionFunction> function =
       new api::DeveloperPrivateDeleteExtensionErrorsFunction();
   EXPECT_TRUE(RunFunction(function, *args)) << function->GetError();
   // Two errors should remain.
@@ -1123,7 +1123,7 @@
   // Attempt to repair the good extension, expect failure.
   std::unique_ptr<base::ListValue> args =
       ListBuilder().Append(extension->id()).Build();
-  scoped_refptr<UIThreadExtensionFunction> function =
+  scoped_refptr<ExtensionFunction> function =
       new api::DeveloperPrivateRepairExtensionFunction();
   EXPECT_FALSE(RunFunction(function, *args));
   EXPECT_EQ("Cannot repair a healthy extension.", function->GetError());
@@ -1154,7 +1154,7 @@
   // Attempt to repair the good extension, expect failure.
   std::unique_ptr<base::ListValue> args =
       ListBuilder().Append(extension_id).Build();
-  scoped_refptr<UIThreadExtensionFunction> function =
+  scoped_refptr<ExtensionFunction> function =
       new api::DeveloperPrivateRepairExtensionFunction();
   EXPECT_FALSE(RunFunction(function, *args));
   EXPECT_EQ("Cannot repair a healthy extension.", function->GetError());
@@ -1219,7 +1219,7 @@
 
   PrefService* prefs = profile()->GetPrefs();
   prefs->SetBoolean(prefs::kExtensionsUIDeveloperMode, false);
-  scoped_refptr<UIThreadExtensionFunction> function =
+  scoped_refptr<ExtensionFunction> function =
       base::MakeRefCounted<api::DeveloperPrivateLoadUnpackedFunction>();
   function->SetRenderFrameHost(web_contents->GetMainFrame());
   std::string error = extension_function_test_utils::RunFunctionAndReturnError(
@@ -1252,7 +1252,7 @@
 
   EXPECT_FALSE(info->can_load_unpacked);
 
-  scoped_refptr<UIThreadExtensionFunction> function =
+  scoped_refptr<ExtensionFunction> function =
       base::MakeRefCounted<api::DeveloperPrivateLoadUnpackedFunction>();
   function->SetRenderFrameHost(web_contents->GetMainFrame());
   std::string error = extension_function_test_utils::RunFunctionAndReturnError(
@@ -1295,7 +1295,7 @@
   std::unique_ptr<content::WebContents> web_contents(
       content::WebContentsTester::CreateTestWebContents(profile(), nullptr));
 
-  scoped_refptr<UIThreadExtensionFunction> function =
+  scoped_refptr<ExtensionFunction> function =
       base::MakeRefCounted<api::DeveloperPrivateInstallDroppedFileFunction>();
   function->SetRenderFrameHost(web_contents->GetMainFrame());
 
@@ -1321,7 +1321,7 @@
   DeveloperPrivateAPI::Get(profile())->SetDraggedPath(web_contents.get(),
                                                       crx_path);
 
-  scoped_refptr<UIThreadExtensionFunction> function =
+  scoped_refptr<ExtensionFunction> function =
       base::MakeRefCounted<api::DeveloperPrivateInstallDroppedFileFunction>();
   function->SetRenderFrameHost(web_contents->GetMainFrame());
 
@@ -1344,7 +1344,7 @@
   DeveloperPrivateAPI::Get(profile())->SetDraggedPath(web_contents.get(),
                                                       script_path);
 
-  scoped_refptr<UIThreadExtensionFunction> function =
+  scoped_refptr<ExtensionFunction> function =
       base::MakeRefCounted<api::DeveloperPrivateInstallDroppedFileFunction>();
   function->SetRenderFrameHost(web_contents->GetMainFrame());
 
@@ -1368,7 +1368,7 @@
                                                    bool should_succeed,
                                                    const char* expected_error) {
     SCOPED_TRACE(host);
-    scoped_refptr<UIThreadExtensionFunction> function =
+    scoped_refptr<ExtensionFunction> function =
         base::MakeRefCounted<api::DeveloperPrivateAddHostPermissionFunction>();
 
     std::string args = base::StringPrintf(R"(["%s", "%s"])",
@@ -1425,7 +1425,7 @@
                                         bool should_succeed,
                                         const char* expected_error) {
     SCOPED_TRACE(host);
-    scoped_refptr<UIThreadExtensionFunction> function = base::MakeRefCounted<
+    scoped_refptr<ExtensionFunction> function = base::MakeRefCounted<
         api::DeveloperPrivateRemoveHostPermissionFunction>();
     std::string args = base::StringPrintf(R"(["%s", "%s"])",
                                           extension->id().c_str(), host.data());
@@ -1579,7 +1579,7 @@
             *extension_prefs->GetRuntimeGrantedPermissions(extension->id()));
 
   {
-    scoped_refptr<UIThreadExtensionFunction> function =
+    scoped_refptr<ExtensionFunction> function =
         base::MakeRefCounted<api::DeveloperPrivateAddHostPermissionFunction>();
     std::string args = base::StringPrintf(
         R"(["%s", "%s"])", extension->id().c_str(), "*://chromium.org/*");
@@ -1610,7 +1610,7 @@
             *extension_prefs->GetRuntimeGrantedPermissions(extension->id()));
 
   {
-    scoped_refptr<UIThreadExtensionFunction> function = base::MakeRefCounted<
+    scoped_refptr<ExtensionFunction> function = base::MakeRefCounted<
         api::DeveloperPrivateRemoveHostPermissionFunction>();
     std::string args = base::StringPrintf(
         R"(["%s", "%s"])", extension->id().c_str(), "*://chromium.org/*");
@@ -1730,7 +1730,7 @@
   DeveloperPrivateAPI::Get(profile())->SetDraggedPath(web_contents.get(),
                                                       zip_path);
 
-  scoped_refptr<UIThreadExtensionFunction> function =
+  scoped_refptr<ExtensionFunction> function =
       base::MakeRefCounted<api::DeveloperPrivateInstallDroppedFileFunction>();
   function->SetRenderFrameHost(web_contents->GetMainFrame());
 
@@ -1765,7 +1765,7 @@
 
   ASSERT_TRUE(profile()->IsSupervised());
 
-  scoped_refptr<UIThreadExtensionFunction> function =
+  scoped_refptr<ExtensionFunction> function =
       base::MakeRefCounted<api::DeveloperPrivateLoadUnpackedFunction>();
   function->SetRenderFrameHost(web_contents->GetMainFrame());
   std::string error = extension_function_test_utils::RunFunctionAndReturnError(
diff --git a/chrome/browser/extensions/api/developer_private/developer_private_apitest.cc b/chrome/browser/extensions/api/developer_private/developer_private_apitest.cc
index 570844d..f4cb2836 100644
--- a/chrome/browser/extensions/api/developer_private/developer_private_apitest.cc
+++ b/chrome/browser/extensions/api/developer_private/developer_private_apitest.cc
@@ -43,7 +43,7 @@
   const Extension* app = LoadAndLaunchApp(dir);
 
   // Get the info about the app, including the inspectable views.
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivateGetExtensionInfoFunction());
   std::unique_ptr<base::Value> result(
       extension_function_test_utils::RunFunctionAndReturnSingleResult(
@@ -97,7 +97,7 @@
   WaitForExtensionNotIdle(extension->id());
 
   // Get the info about the extension, including the inspectable views.
-  scoped_refptr<UIThreadExtensionFunction> function(
+  scoped_refptr<ExtensionFunction> function(
       new api::DeveloperPrivateGetExtensionInfoFunction());
   std::unique_ptr<base::Value> result(
       extension_function_test_utils::RunFunctionAndReturnSingleResult(
diff --git a/chrome/browser/extensions/api/downloads/downloads_api.h b/chrome/browser/extensions/api/downloads/downloads_api.h
index 7a44733..81d3cc6 100644
--- a/chrome/browser/extensions/api/downloads/downloads_api.h
+++ b/chrome/browser/extensions/api/downloads/downloads_api.h
@@ -107,7 +107,7 @@
   DISALLOW_COPY_AND_ASSIGN(DownloadsDownloadFunction);
 };
 
-class DownloadsSearchFunction : public UIThreadExtensionFunction {
+class DownloadsSearchFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("downloads.search", DOWNLOADS_SEARCH)
   DownloadsSearchFunction();
@@ -120,7 +120,7 @@
   DISALLOW_COPY_AND_ASSIGN(DownloadsSearchFunction);
 };
 
-class DownloadsPauseFunction : public UIThreadExtensionFunction {
+class DownloadsPauseFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("downloads.pause", DOWNLOADS_PAUSE)
   DownloadsPauseFunction();
@@ -133,7 +133,7 @@
   DISALLOW_COPY_AND_ASSIGN(DownloadsPauseFunction);
 };
 
-class DownloadsResumeFunction : public UIThreadExtensionFunction {
+class DownloadsResumeFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("downloads.resume", DOWNLOADS_RESUME)
   DownloadsResumeFunction();
@@ -146,7 +146,7 @@
   DISALLOW_COPY_AND_ASSIGN(DownloadsResumeFunction);
 };
 
-class DownloadsCancelFunction : public UIThreadExtensionFunction {
+class DownloadsCancelFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("downloads.cancel", DOWNLOADS_CANCEL)
   DownloadsCancelFunction();
@@ -159,7 +159,7 @@
   DISALLOW_COPY_AND_ASSIGN(DownloadsCancelFunction);
 };
 
-class DownloadsEraseFunction : public UIThreadExtensionFunction {
+class DownloadsEraseFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("downloads.erase", DOWNLOADS_ERASE)
   DownloadsEraseFunction();
@@ -211,7 +211,7 @@
   DISALLOW_COPY_AND_ASSIGN(DownloadsAcceptDangerFunction);
 };
 
-class DownloadsShowFunction : public UIThreadExtensionFunction {
+class DownloadsShowFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("downloads.show", DOWNLOADS_SHOW)
   DownloadsShowFunction();
@@ -224,7 +224,7 @@
   DISALLOW_COPY_AND_ASSIGN(DownloadsShowFunction);
 };
 
-class DownloadsShowDefaultFolderFunction : public UIThreadExtensionFunction {
+class DownloadsShowDefaultFolderFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION(
       "downloads.showDefaultFolder", DOWNLOADS_SHOWDEFAULTFOLDER)
@@ -238,7 +238,7 @@
   DISALLOW_COPY_AND_ASSIGN(DownloadsShowDefaultFolderFunction);
 };
 
-class DownloadsOpenFunction : public UIThreadExtensionFunction {
+class DownloadsOpenFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("downloads.open", DOWNLOADS_OPEN)
   DownloadsOpenFunction();
@@ -261,7 +261,7 @@
   DISALLOW_COPY_AND_ASSIGN(DownloadsOpenFunction);
 };
 
-class DownloadsSetShelfEnabledFunction : public UIThreadExtensionFunction {
+class DownloadsSetShelfEnabledFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("downloads.setShelfEnabled",
                              DOWNLOADS_SETSHELFENABLED)
@@ -275,7 +275,7 @@
   DISALLOW_COPY_AND_ASSIGN(DownloadsSetShelfEnabledFunction);
 };
 
-class DownloadsDragFunction : public UIThreadExtensionFunction {
+class DownloadsDragFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("downloads.drag", DOWNLOADS_DRAG)
   DownloadsDragFunction();
diff --git a/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc b/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc
index fec35ae..2575f45 100644
--- a/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc
+++ b/chrome/browser/extensions/api/downloads/downloads_api_browsertest.cc
@@ -599,9 +599,8 @@
         GetCurrentManager(), download_count);
   }
 
-  bool RunFunction(UIThreadExtensionFunction* function,
-                   const std::string& args) {
-    scoped_refptr<UIThreadExtensionFunction> delete_function(function);
+  bool RunFunction(ExtensionFunction* function, const std::string& args) {
+    scoped_refptr<ExtensionFunction> delete_function(function);
     SetUpExtensionFunction(function);
     bool result = extension_function_test_utils::RunFunction(
         function, args, current_browser(), GetFlags());
@@ -622,7 +621,7 @@
   // on-record profile to match real-life behavior.
 
   base::Value* RunFunctionAndReturnResult(
-      scoped_refptr<UIThreadExtensionFunction> function,
+      scoped_refptr<ExtensionFunction> function,
       const std::string& args) {
     SetUpExtensionFunction(function.get());
     return extension_function_test_utils::RunFunctionAndReturnSingleResult(
@@ -630,17 +629,16 @@
   }
 
   std::string RunFunctionAndReturnError(
-      scoped_refptr<UIThreadExtensionFunction> function,
+      scoped_refptr<ExtensionFunction> function,
       const std::string& args) {
     SetUpExtensionFunction(function.get());
     return extension_function_test_utils::RunFunctionAndReturnError(
         function.get(), args, current_browser(), GetFlags());
   }
 
-  bool RunFunctionAndReturnString(
-      scoped_refptr<UIThreadExtensionFunction> function,
-      const std::string& args,
-      std::string* result_string) {
+  bool RunFunctionAndReturnString(scoped_refptr<ExtensionFunction> function,
+                                  const std::string& args,
+                                  std::string* result_string) {
     SetUpExtensionFunction(function.get());
     std::unique_ptr<base::Value> result(
         RunFunctionAndReturnResult(function, args));
@@ -661,7 +659,7 @@
   const Extension* extension() { return extension_; }
 
  private:
-  void SetUpExtensionFunction(UIThreadExtensionFunction* function) {
+  void SetUpExtensionFunction(ExtensionFunction* function) {
     if (extension_) {
       const GURL url = current_browser_ == incognito_browser_ &&
                                !IncognitoInfo::IsSplitMode(extension_)
@@ -1044,7 +1042,7 @@
   EXPECT_EQ(id, element);
 }
 
-scoped_refptr<UIThreadExtensionFunction> MockedGetFileIconFunction(
+scoped_refptr<ExtensionFunction> MockedGetFileIconFunction(
     const base::FilePath& expected_path,
     IconLoader::IconSize icon_size,
     const std::string& response) {
diff --git a/chrome/browser/extensions/api/downloads_internal/downloads_internal_api.h b/chrome/browser/extensions/api/downloads_internal/downloads_internal_api.h
index 639906d..490c94e 100644
--- a/chrome/browser/extensions/api/downloads_internal/downloads_internal_api.h
+++ b/chrome/browser/extensions/api/downloads_internal/downloads_internal_api.h
@@ -10,8 +10,7 @@
 
 namespace extensions {
 
-class DownloadsInternalDetermineFilenameFunction
-    : public UIThreadExtensionFunction {
+class DownloadsInternalDetermineFilenameFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("downloadsInternal.determineFilename",
                              DOWNLOADSINTERNAL_DETERMINEFILENAME)
diff --git a/chrome/browser/extensions/api/enterprise_device_attributes/enterprise_device_attributes_api.h b/chrome/browser/extensions/api/enterprise_device_attributes/enterprise_device_attributes_api.h
index 0f87921..5c6a57c 100644
--- a/chrome/browser/extensions/api/enterprise_device_attributes/enterprise_device_attributes_api.h
+++ b/chrome/browser/extensions/api/enterprise_device_attributes/enterprise_device_attributes_api.h
@@ -10,7 +10,7 @@
 namespace extensions {
 
 class EnterpriseDeviceAttributesGetDirectoryDeviceIdFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   EnterpriseDeviceAttributesGetDirectoryDeviceIdFunction();
 
@@ -25,7 +25,7 @@
 };
 
 class EnterpriseDeviceAttributesGetDeviceSerialNumberFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   EnterpriseDeviceAttributesGetDeviceSerialNumberFunction();
 
@@ -41,7 +41,7 @@
 };
 
 class EnterpriseDeviceAttributesGetDeviceAssetIdFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   EnterpriseDeviceAttributesGetDeviceAssetIdFunction();
 
@@ -56,7 +56,7 @@
 };
 
 class EnterpriseDeviceAttributesGetDeviceAnnotatedLocationFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   EnterpriseDeviceAttributesGetDeviceAnnotatedLocationFunction();
 
diff --git a/chrome/browser/extensions/api/enterprise_hardware_platform/enterprise_hardware_platform_api.h b/chrome/browser/extensions/api/enterprise_hardware_platform/enterprise_hardware_platform_api.h
index 1600ac5..0d69118 100644
--- a/chrome/browser/extensions/api/enterprise_hardware_platform/enterprise_hardware_platform_api.h
+++ b/chrome/browser/extensions/api/enterprise_hardware_platform/enterprise_hardware_platform_api.h
@@ -12,7 +12,7 @@
 namespace extensions {
 
 class EnterpriseHardwarePlatformGetHardwarePlatformInfoFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   EnterpriseHardwarePlatformGetHardwarePlatformInfoFunction();
 
diff --git a/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api.cc b/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api.cc
index 78b8bb0..cc48d23d 100644
--- a/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api.cc
+++ b/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api.cc
@@ -283,7 +283,7 @@
   // |callback| holds a reference to |this|.
   base::Closure task =
       base::Bind(&EPKPChallengeMachineKey::Run, base::Unretained(impl_),
-                 scoped_refptr<UIThreadExtensionFunction>(this), callback,
+                 scoped_refptr<ExtensionFunction>(this), callback,
                  StringFromVector(params->challenge),
                  params->register_key ? *params->register_key : false);
   base::PostTaskWithTraits(FROM_HERE, {content::BrowserThread::UI}, task);
@@ -324,7 +324,7 @@
   // |callback| holds a reference to |this|.
   base::Closure task =
       base::Bind(&EPKPChallengeUserKey::Run, base::Unretained(impl_),
-                 scoped_refptr<UIThreadExtensionFunction>(this), callback,
+                 scoped_refptr<ExtensionFunction>(this), callback,
                  StringFromVector(params->challenge), params->register_key);
   base::PostTaskWithTraits(FROM_HERE, {content::BrowserThread::UI}, task);
   return RespondLater();
diff --git a/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api.h b/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api.h
index 6900eb2..9ec384a2 100644
--- a/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api.h
+++ b/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api.h
@@ -21,7 +21,7 @@
 namespace extensions {
 
 class EnterprisePlatformKeysInternalGenerateKeyFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  private:
   ~EnterprisePlatformKeysInternalGenerateKeyFunction() override;
   ResponseAction Run() override;
@@ -35,8 +35,7 @@
                              ENTERPRISE_PLATFORMKEYSINTERNAL_GENERATEKEY)
 };
 
-class EnterprisePlatformKeysGetCertificatesFunction
-    : public UIThreadExtensionFunction {
+class EnterprisePlatformKeysGetCertificatesFunction : public ExtensionFunction {
  private:
   ~EnterprisePlatformKeysGetCertificatesFunction() override;
   ResponseAction Run() override;
@@ -51,7 +50,7 @@
 };
 
 class EnterprisePlatformKeysImportCertificateFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  private:
   ~EnterprisePlatformKeysImportCertificateFunction() override;
   ResponseAction Run() override;
@@ -65,7 +64,7 @@
 };
 
 class EnterprisePlatformKeysRemoveCertificateFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  private:
   ~EnterprisePlatformKeysRemoveCertificateFunction() override;
   ResponseAction Run() override;
@@ -79,7 +78,7 @@
 };
 
 class EnterprisePlatformKeysInternalGetTokensFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  private:
   ~EnterprisePlatformKeysInternalGetTokensFunction() override;
   ResponseAction Run() override;
@@ -94,7 +93,7 @@
 };
 
 class EnterprisePlatformKeysChallengeMachineKeyFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   EnterprisePlatformKeysChallengeMachineKeyFunction();
   explicit EnterprisePlatformKeysChallengeMachineKeyFunction(
@@ -117,7 +116,7 @@
 };
 
 class EnterprisePlatformKeysChallengeUserKeyFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   EnterprisePlatformKeysChallengeUserKeyFunction();
   explicit EnterprisePlatformKeysChallengeUserKeyFunction(
diff --git a/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api_unittest.cc b/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api_unittest.cc
index 5fa0fffc2..ba3cd7e1 100644
--- a/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api_unittest.cc
+++ b/chrome/browser/extensions/api/enterprise_platform_keys/enterprise_platform_keys_api_unittest.cc
@@ -181,7 +181,7 @@
 
   // Like extension_function_test_utils::RunFunctionAndReturnError but with an
   // explicit ListValue.
-  std::string RunFunctionAndReturnError(UIThreadExtensionFunction* function,
+  std::string RunFunctionAndReturnError(ExtensionFunction* function,
                                         std::unique_ptr<base::ListValue> args,
                                         Browser* browser) {
     utils::RunFunction(function, std::move(args), browser,
@@ -193,7 +193,7 @@
   // Like extension_function_test_utils::RunFunctionAndReturnSingleResult but
   // with an explicit ListValue.
   base::Value* RunFunctionAndReturnSingleResult(
-      UIThreadExtensionFunction* function,
+      ExtensionFunction* function,
       std::unique_ptr<base::ListValue> args,
       Browser* browser) {
     scoped_refptr<ExtensionFunction> function_owner(function);
diff --git a/chrome/browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api.cc b/chrome/browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api.cc
index 14affe2..514a9e0 100644
--- a/chrome/browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api.cc
+++ b/chrome/browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api.cc
@@ -337,11 +337,10 @@
 EPKPChallengeMachineKey::~EPKPChallengeMachineKey() {
 }
 
-void EPKPChallengeMachineKey::Run(
-    scoped_refptr<UIThreadExtensionFunction> caller,
-    const ChallengeKeyCallback& callback,
-    const std::string& challenge,
-    bool register_key) {
+void EPKPChallengeMachineKey::Run(scoped_refptr<ExtensionFunction> caller,
+                                  const ChallengeKeyCallback& callback,
+                                  const std::string& challenge,
+                                  bool register_key) {
   callback_ = callback;
   profile_ = ChromeExtensionFunctionDetails(caller.get()).GetProfile();
   extension_ = scoped_refptr<const Extension>(caller->extension());
@@ -372,7 +371,7 @@
 }
 
 void EPKPChallengeMachineKey::DecodeAndRun(
-    scoped_refptr<UIThreadExtensionFunction> caller,
+    scoped_refptr<ExtensionFunction> caller,
     const ChallengeKeyCallback& callback,
     const std::string& encoded_challenge,
     bool register_key) {
@@ -489,7 +488,7 @@
   registry->RegisterListPref(prefs::kAttestationExtensionWhitelist);
 }
 
-void EPKPChallengeUserKey::Run(scoped_refptr<UIThreadExtensionFunction> caller,
+void EPKPChallengeUserKey::Run(scoped_refptr<ExtensionFunction> caller,
                                const ChallengeKeyCallback& callback,
                                const std::string& challenge,
                                bool register_key) {
@@ -535,11 +534,10 @@
   }
 }
 
-void EPKPChallengeUserKey::DecodeAndRun(
-    scoped_refptr<UIThreadExtensionFunction> caller,
-    const ChallengeKeyCallback& callback,
-    const std::string& encoded_challenge,
-    bool register_key) {
+void EPKPChallengeUserKey::DecodeAndRun(scoped_refptr<ExtensionFunction> caller,
+                                        const ChallengeKeyCallback& callback,
+                                        const std::string& encoded_challenge,
+                                        bool register_key) {
   std::string challenge;
   if (!base::Base64Decode(encoded_challenge, &challenge)) {
     callback.Run(false, kChallengeBadBase64Error);
@@ -645,10 +643,10 @@
                  this);
   // base::Unretained is safe on impl_ since its life-cycle matches |this| and
   // |callback| holds a reference to |this|.
-  base::Closure task = base::Bind(
-      &EPKPChallengeMachineKey::DecodeAndRun, base::Unretained(impl_),
-      scoped_refptr<UIThreadExtensionFunction>(this), callback,
-      params->challenge, false);
+  base::Closure task = base::Bind(&EPKPChallengeMachineKey::DecodeAndRun,
+                                  base::Unretained(impl_),
+                                  scoped_refptr<ExtensionFunction>(this),
+                                  callback, params->challenge, false);
   base::PostTaskWithTraits(FROM_HERE, {content::BrowserThread::UI}, task);
   return RespondLater();
 }
@@ -690,7 +688,7 @@
   // |callback| holds a reference to |this|.
   base::Closure task =
       base::Bind(&EPKPChallengeUserKey::DecodeAndRun, base::Unretained(impl_),
-                 scoped_refptr<UIThreadExtensionFunction>(this), callback,
+                 scoped_refptr<ExtensionFunction>(this), callback,
                  params->challenge, params->register_key);
   base::PostTaskWithTraits(FROM_HERE, {content::BrowserThread::UI}, task);
   return RespondLater();
diff --git a/chrome/browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api.h b/chrome/browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api.h
index 66cb475..460ed7b 100644
--- a/chrome/browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api.h
+++ b/chrome/browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api.h
@@ -176,13 +176,13 @@
 
   // Asynchronously run the flow to challenge a machine key in the |caller|
   // context.
-  void Run(scoped_refptr<UIThreadExtensionFunction> caller,
+  void Run(scoped_refptr<ExtensionFunction> caller,
            const ChallengeKeyCallback& callback,
            const std::string& encoded_challenge,
            bool register_key);
 
   // Like |Run| but expects a Base64 |encoded_challenge|.
-  void DecodeAndRun(scoped_refptr<UIThreadExtensionFunction> caller,
+  void DecodeAndRun(scoped_refptr<ExtensionFunction> caller,
                     const ChallengeKeyCallback& callback,
                     const std::string& encoded_challenge,
                     bool register_key);
@@ -223,13 +223,13 @@
 
   // Asynchronously run the flow to challenge a user key in the |caller|
   // context.
-  void Run(scoped_refptr<UIThreadExtensionFunction> caller,
+  void Run(scoped_refptr<ExtensionFunction> caller,
            const ChallengeKeyCallback& callback,
            const std::string& challenge,
            bool register_key);
 
   // Like |Run| but expects a Base64 |encoded_challenge|.
-  void DecodeAndRun(scoped_refptr<UIThreadExtensionFunction> caller,
+  void DecodeAndRun(scoped_refptr<ExtensionFunction> caller,
                     const ChallengeKeyCallback& callback,
                     const std::string& encoded_challenge,
                     bool register_key);
@@ -255,7 +255,7 @@
 };
 
 class EnterprisePlatformKeysPrivateChallengeMachineKeyFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   EnterprisePlatformKeysPrivateChallengeMachineKeyFunction();
   explicit EnterprisePlatformKeysPrivateChallengeMachineKeyFunction(
@@ -279,7 +279,7 @@
 };
 
 class EnterprisePlatformKeysPrivateChallengeUserKeyFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   EnterprisePlatformKeysPrivateChallengeUserKeyFunction();
   explicit EnterprisePlatformKeysPrivateChallengeUserKeyFunction(
diff --git a/chrome/browser/extensions/api/enterprise_reporting_private/enterprise_reporting_private_api.h b/chrome/browser/extensions/api/enterprise_reporting_private/enterprise_reporting_private_api.h
index c6ebd8fa..ec772107 100644
--- a/chrome/browser/extensions/api/enterprise_reporting_private/enterprise_reporting_private_api.h
+++ b/chrome/browser/extensions/api/enterprise_reporting_private/enterprise_reporting_private_api.h
@@ -27,7 +27,7 @@
 }  // namespace enterprise_reporting
 
 class EnterpriseReportingPrivateUploadChromeDesktopReportFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION(
       "enterprise.reportingPrivate.uploadChromeDesktopReport",
@@ -65,8 +65,7 @@
       EnterpriseReportingPrivateUploadChromeDesktopReportFunction);
 };
 
-class EnterpriseReportingPrivateGetDeviceIdFunction
-    : public UIThreadExtensionFunction {
+class EnterpriseReportingPrivateGetDeviceIdFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("enterprise.reportingPrivate.getDeviceId",
                              ENTERPRISEREPORTINGPRIVATE_GETDEVICEID)
diff --git a/chrome/browser/extensions/api/enterprise_reporting_private/enterprise_reporting_private_unittest.cc b/chrome/browser/extensions/api/enterprise_reporting_private/enterprise_reporting_private_unittest.cc
index bca47a1..344b323 100644
--- a/chrome/browser/extensions/api/enterprise_reporting_private/enterprise_reporting_private_unittest.cc
+++ b/chrome/browser/extensions/api/enterprise_reporting_private/enterprise_reporting_private_unittest.cc
@@ -34,7 +34,7 @@
  public:
   EnterpriseReportingPrivateUploadChromeDesktopReportTest() {}
 
-  UIThreadExtensionFunction* CreateChromeDesktopReportingFunction(
+  ExtensionFunction* CreateChromeDesktopReportingFunction(
       const std::string& dm_token) {
     EnterpriseReportingPrivateUploadChromeDesktopReportFunction* function =
         EnterpriseReportingPrivateUploadChromeDesktopReportFunction::
@@ -85,7 +85,7 @@
 }
 
 TEST_F(EnterpriseReportingPrivateUploadChromeDesktopReportTest, UploadFailed) {
-  UIThreadExtensionFunction* function =
+  ExtensionFunction* function =
       CreateChromeDesktopReportingFunction(kFakeDMToken);
   EXPECT_CALL(*client_, SetupRegistration(kFakeDMToken, kFakeClientId, _))
       .Times(1);
@@ -99,7 +99,7 @@
 
 TEST_F(EnterpriseReportingPrivateUploadChromeDesktopReportTest,
        UploadSucceeded) {
-  UIThreadExtensionFunction* function =
+  ExtensionFunction* function =
       CreateChromeDesktopReportingFunction(kFakeDMToken);
   EXPECT_CALL(*client_, SetupRegistration(kFakeDMToken, kFakeClientId, _))
       .Times(1);
diff --git a/chrome/browser/extensions/api/extension_action/extension_action_api.h b/chrome/browser/extensions/api/extension_action/extension_action_api.h
index a5910ca..6ae7ffb 100644
--- a/chrome/browser/extensions/api/extension_action/extension_action_api.h
+++ b/chrome/browser/extensions/api/extension_action/extension_action_api.h
@@ -126,7 +126,7 @@
 // tabIds while browserAction's are optional, they have different internal
 // browser notification requirements, and not all functions are defined for all
 // APIs).
-class ExtensionActionFunction : public UIThreadExtensionFunction {
+class ExtensionActionFunction : public ExtensionFunction {
  public:
   static bool ParseCSSColorString(const std::string& color_string,
                                   SkColor* result);
@@ -442,7 +442,7 @@
   ~BrowserActionDisableFunction() override {}
 };
 
-class BrowserActionOpenPopupFunction : public UIThreadExtensionFunction,
+class BrowserActionOpenPopupFunction : public ExtensionFunction,
                                        public content::NotificationObserver {
  public:
   DECLARE_EXTENSION_FUNCTION("browserAction.openPopup",
diff --git a/chrome/browser/extensions/api/file_system/chrome_file_system_delegate.cc b/chrome/browser/extensions/api/file_system/chrome_file_system_delegate.cc
index b440c80..c5c066e 100644
--- a/chrome/browser/extensions/api/file_system/chrome_file_system_delegate.cc
+++ b/chrome/browser/extensions/api/file_system/chrome_file_system_delegate.cc
@@ -106,7 +106,7 @@
 // Callback called when consent is granted or denied.
 void OnConsentReceived(
     content::BrowserContext* browser_context,
-    scoped_refptr<UIThreadExtensionFunction> requester,
+    scoped_refptr<ExtensionFunction> requester,
     const FileSystemDelegate::FileSystemCallback& success_callback,
     const FileSystemDelegate::ErrorCallback& error_callback,
     const std::string& extension_id,
@@ -252,7 +252,7 @@
 }
 
 bool ChromeFileSystemDelegate::ShowSelectFileDialog(
-    scoped_refptr<UIThreadExtensionFunction> extension_function,
+    scoped_refptr<ExtensionFunction> extension_function,
     ui::SelectFileDialog::Type type,
     const base::FilePath& default_path,
     const ui::SelectFileDialog::FileTypeInfo* file_types,
@@ -282,7 +282,7 @@
     return false;
   }
 
-  // The file picker will hold a reference to the UIThreadExtensionFunction
+  // The file picker will hold a reference to the ExtensionFunction
   // instance, preventing its destruction (and subsequent sending of the
   // function response) until the user has selected a file or cancelled the
   // picker. At that point, the picker will delete itself, which will also free
@@ -330,7 +330,7 @@
 
 void ChromeFileSystemDelegate::RequestFileSystem(
     content::BrowserContext* browser_context,
-    scoped_refptr<UIThreadExtensionFunction> requester,
+    scoped_refptr<ExtensionFunction> requester,
     const Extension& extension,
     std::string volume_id,
     bool writable,
diff --git a/chrome/browser/extensions/api/file_system/chrome_file_system_delegate.h b/chrome/browser/extensions/api/file_system/chrome_file_system_delegate.h
index 9dd8784b..a127639 100644
--- a/chrome/browser/extensions/api/file_system/chrome_file_system_delegate.h
+++ b/chrome/browser/extensions/api/file_system/chrome_file_system_delegate.h
@@ -32,7 +32,7 @@
   // FileSystemDelegate:
   base::FilePath GetDefaultDirectory() override;
   bool ShowSelectFileDialog(
-      scoped_refptr<UIThreadExtensionFunction> extension_function,
+      scoped_refptr<ExtensionFunction> extension_function,
       ui::SelectFileDialog::Type type,
       const base::FilePath& default_path,
       const ui::SelectFileDialog::FileTypeInfo* file_types,
@@ -50,7 +50,7 @@
       content::RenderFrameHost* render_frame_host,
       const Extension& extension) override;
   void RequestFileSystem(content::BrowserContext* browser_context,
-                         scoped_refptr<UIThreadExtensionFunction> requester,
+                         scoped_refptr<ExtensionFunction> requester,
                          const Extension& extension,
                          std::string volume_id,
                          bool writable,
diff --git a/chrome/browser/extensions/api/font_settings/font_settings_api.h b/chrome/browser/extensions/api/font_settings/font_settings_api.h
index 880218a..6b206d4 100644
--- a/chrome/browser/extensions/api/font_settings/font_settings_api.h
+++ b/chrome/browser/extensions/api/font_settings/font_settings_api.h
@@ -101,7 +101,7 @@
 };
 
 // fontSettings.clearFont API function.
-class FontSettingsClearFontFunction : public UIThreadExtensionFunction {
+class FontSettingsClearFontFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fontSettings.clearFont", FONTSETTINGS_CLEARFONT)
 
@@ -115,7 +115,7 @@
 };
 
 // fontSettings.getFont API function.
-class FontSettingsGetFontFunction : public UIThreadExtensionFunction {
+class FontSettingsGetFontFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fontSettings.getFont", FONTSETTINGS_GETFONT)
 
@@ -127,7 +127,7 @@
 };
 
 // fontSettings.setFont API function.
-class FontSettingsSetFontFunction : public UIThreadExtensionFunction {
+class FontSettingsSetFontFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("fontSettings.setFont", FONTSETTINGS_SETFONT)
 
@@ -156,7 +156,7 @@
 };
 
 // Base class for extension API functions that clear a browser font pref.
-class ClearFontPrefExtensionFunction : public UIThreadExtensionFunction {
+class ClearFontPrefExtensionFunction : public ExtensionFunction {
  protected:
   ~ClearFontPrefExtensionFunction() override {}
 
@@ -169,7 +169,7 @@
 };
 
 // Base class for extension API functions that get a browser font pref.
-class GetFontPrefExtensionFunction : public UIThreadExtensionFunction {
+class GetFontPrefExtensionFunction : public ExtensionFunction {
  protected:
   ~GetFontPrefExtensionFunction() override {}
 
@@ -186,7 +186,7 @@
 };
 
 // Base class for extension API functions that set a browser font pref.
-class SetFontPrefExtensionFunction : public UIThreadExtensionFunction {
+class SetFontPrefExtensionFunction : public ExtensionFunction {
  protected:
   ~SetFontPrefExtensionFunction() override {}
 
diff --git a/chrome/browser/extensions/api/gcm/gcm_api.h b/chrome/browser/extensions/api/gcm/gcm_api.h
index 40bbd1b..8e538f66 100644
--- a/chrome/browser/extensions/api/gcm/gcm_api.h
+++ b/chrome/browser/extensions/api/gcm/gcm_api.h
@@ -17,7 +17,7 @@
 
 namespace extensions {
 
-class GcmApiFunction : public UIThreadExtensionFunction {
+class GcmApiFunction : public ExtensionFunction {
  public:
   GcmApiFunction() {}
 
@@ -42,7 +42,7 @@
  protected:
   ~GcmRegisterFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() final;
 
  private:
@@ -59,7 +59,7 @@
  protected:
   ~GcmUnregisterFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() final;
 
  private:
@@ -75,7 +75,7 @@
  protected:
   ~GcmSendFunction() override;
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() final;
 
  private:
diff --git a/chrome/browser/extensions/api/history/history_api.h b/chrome/browser/extensions/api/history/history_api.h
index 9a0433db..5349fca 100644
--- a/chrome/browser/extensions/api/history/history_api.h
+++ b/chrome/browser/extensions/api/history/history_api.h
@@ -93,7 +93,7 @@
 void BrowserContextKeyedAPIFactory<HistoryAPI>::DeclareFactoryDependencies();
 
 // Base class for history function APIs.
-class HistoryFunction : public UIThreadExtensionFunction {
+class HistoryFunction : public ExtensionFunction {
  protected:
   ~HistoryFunction() override {}
 
diff --git a/chrome/browser/extensions/api/i18n/i18n_api.h b/chrome/browser/extensions/api/i18n/i18n_api.h
index 5576a363..88ed709 100644
--- a/chrome/browser/extensions/api/i18n/i18n_api.h
+++ b/chrome/browser/extensions/api/i18n/i18n_api.h
@@ -9,7 +9,7 @@
 
 namespace extensions {
 
-class I18nGetAcceptLanguagesFunction : public UIThreadExtensionFunction {
+class I18nGetAcceptLanguagesFunction : public ExtensionFunction {
   ~I18nGetAcceptLanguagesFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("i18n.getAcceptLanguages", I18N_GETACCEPTLANGUAGES)
diff --git a/chrome/browser/extensions/api/identity/identity_apitest.cc b/chrome/browser/extensions/api/identity/identity_apitest.cc
index 99e6d39..ef79b4e6 100644
--- a/chrome/browser/extensions/api/identity/identity_apitest.cc
+++ b/chrome/browser/extensions/api/identity/identity_apitest.cc
@@ -89,7 +89,7 @@
 // after the call happens.
 class AsyncFunctionRunner {
  public:
-  void RunFunctionAsync(UIThreadExtensionFunction* function,
+  void RunFunctionAsync(ExtensionFunction* function,
                         const std::string& args,
                         content::BrowserContext* browser_context) {
     response_delegate_.reset(new api_test_utils::SendResponseHelper(function));
@@ -109,14 +109,14 @@
     function->RunWithValidation()->Execute();
   }
 
-  std::string WaitForError(UIThreadExtensionFunction* function) {
+  std::string WaitForError(ExtensionFunction* function) {
     RunMessageLoopUntilResponse();
     CHECK(function->response_type());
     EXPECT_EQ(ExtensionFunction::FAILED, *function->response_type());
     return function->GetError();
   }
 
-  base::Value* WaitForSingleResult(UIThreadExtensionFunction* function) {
+  base::Value* WaitForSingleResult(ExtensionFunction* function) {
     RunMessageLoopUntilResponse();
     EXPECT_TRUE(function->GetError().empty())
         << "Unexpected error: " << function->GetError();
@@ -140,18 +140,17 @@
 class AsyncExtensionBrowserTest : public ExtensionBrowserTest {
  protected:
   // Provide wrappers of AsynchronousFunctionRunner for convenience.
-  void RunFunctionAsync(UIThreadExtensionFunction* function,
-                        const std::string& args) {
+  void RunFunctionAsync(ExtensionFunction* function, const std::string& args) {
     async_function_runner_ = std::make_unique<AsyncFunctionRunner>();
     async_function_runner_->RunFunctionAsync(function, args,
                                              browser()->profile());
   }
 
-  std::string WaitForError(UIThreadExtensionFunction* function) {
+  std::string WaitForError(ExtensionFunction* function) {
     return async_function_runner_->WaitForError(function);
   }
 
-  base::Value* WaitForSingleResult(UIThreadExtensionFunction* function) {
+  base::Value* WaitForSingleResult(ExtensionFunction* function) {
     return async_function_runner_->WaitForSingleResult(function);
   }
 
diff --git a/chrome/browser/extensions/api/identity/identity_get_accounts_function.h b/chrome/browser/extensions/api/identity/identity_get_accounts_function.h
index a123670..1b8c765 100644
--- a/chrome/browser/extensions/api/identity/identity_get_accounts_function.h
+++ b/chrome/browser/extensions/api/identity/identity_get_accounts_function.h
@@ -10,7 +10,7 @@
 
 namespace extensions {
 
-class IdentityGetAccountsFunction : public UIThreadExtensionFunction {
+class IdentityGetAccountsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("identity.getAccounts", IDENTITY_GETACCOUNTS)
 
@@ -19,7 +19,7 @@
  private:
   ~IdentityGetAccountsFunction() override;
 
-  // UIThreadExtensionFunction implementation.
+  // ExtensionFunction implementation.
   ExtensionFunction::ResponseAction Run() override;
 };
 
diff --git a/chrome/browser/extensions/api/identity/identity_get_profile_user_info_function.h b/chrome/browser/extensions/api/identity/identity_get_profile_user_info_function.h
index f68ecc9..84edc0d 100644
--- a/chrome/browser/extensions/api/identity/identity_get_profile_user_info_function.h
+++ b/chrome/browser/extensions/api/identity/identity_get_profile_user_info_function.h
@@ -10,7 +10,7 @@
 
 namespace extensions {
 
-class IdentityGetProfileUserInfoFunction : public UIThreadExtensionFunction {
+class IdentityGetProfileUserInfoFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("identity.getProfileUserInfo",
                              IDENTITY_GETPROFILEUSERINFO)
@@ -20,7 +20,7 @@
  private:
   ~IdentityGetProfileUserInfoFunction() override;
 
-  // UIThreadExtensionFunction implementation.
+  // ExtensionFunction implementation.
   ExtensionFunction::ResponseAction Run() override;
 };
 
diff --git a/chrome/browser/extensions/api/identity/identity_remove_cached_auth_token_function.h b/chrome/browser/extensions/api/identity/identity_remove_cached_auth_token_function.h
index 710c2eef..e99b464 100644
--- a/chrome/browser/extensions/api/identity/identity_remove_cached_auth_token_function.h
+++ b/chrome/browser/extensions/api/identity/identity_remove_cached_auth_token_function.h
@@ -10,7 +10,7 @@
 
 namespace extensions {
 
-class IdentityRemoveCachedAuthTokenFunction : public UIThreadExtensionFunction {
+class IdentityRemoveCachedAuthTokenFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("identity.removeCachedAuthToken",
                              EXPERIMENTAL_IDENTITY_REMOVECACHEDAUTHTOKEN)
diff --git a/chrome/browser/extensions/api/idltest/idltest_api.h b/chrome/browser/extensions/api/idltest/idltest_api.h
index 48b5e9d..5219e3e 100644
--- a/chrome/browser/extensions/api/idltest/idltest_api.h
+++ b/chrome/browser/extensions/api/idltest/idltest_api.h
@@ -7,7 +7,7 @@
 
 #include "extensions/browser/extension_function.h"
 
-class IdltestSendArrayBufferFunction : public UIThreadExtensionFunction {
+class IdltestSendArrayBufferFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("idltest.sendArrayBuffer", IDLTEST_SENDARRAYBUFFER)
 
@@ -16,7 +16,7 @@
   ResponseAction Run() override;
 };
 
-class IdltestSendArrayBufferViewFunction : public UIThreadExtensionFunction {
+class IdltestSendArrayBufferViewFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("idltest.sendArrayBufferView",
                              IDLTEST_SENDARRAYBUFFERVIEW)
@@ -26,7 +26,7 @@
   ResponseAction Run() override;
 };
 
-class IdltestGetArrayBufferFunction : public UIThreadExtensionFunction {
+class IdltestGetArrayBufferFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("idltest.getArrayBuffer", IDLTEST_GETARRAYBUFFER)
 
diff --git a/chrome/browser/extensions/api/input_ime/input_ime_api.h b/chrome/browser/extensions/api/input_ime/input_ime_api.h
index 78e9fce74..c3fc3b3 100644
--- a/chrome/browser/extensions/api/input_ime/input_ime_api.h
+++ b/chrome/browser/extensions/api/input_ime/input_ime_api.h
@@ -128,7 +128,7 @@
   DISALLOW_COPY_AND_ASSIGN(InputImeEventRouterFactory);
 };
 
-class InputImeKeyEventHandledFunction : public UIThreadExtensionFunction {
+class InputImeKeyEventHandledFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.keyEventHandled",
                              INPUT_IME_KEYEVENTHANDLED)
@@ -136,11 +136,11 @@
  protected:
   ~InputImeKeyEventHandledFunction() override {}
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 };
 
-class InputImeSetCompositionFunction : public UIThreadExtensionFunction {
+class InputImeSetCompositionFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.setComposition",
                              INPUT_IME_SETCOMPOSITION)
@@ -148,29 +148,29 @@
  protected:
   ~InputImeSetCompositionFunction() override {}
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 };
 
-class InputImeCommitTextFunction : public UIThreadExtensionFunction {
+class InputImeCommitTextFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.commitText", INPUT_IME_COMMITTEXT)
 
  protected:
   ~InputImeCommitTextFunction() override {}
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 };
 
-class InputImeSendKeyEventsFunction : public UIThreadExtensionFunction {
+class InputImeSendKeyEventsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.sendKeyEvents", INPUT_IME_SENDKEYEVENTS)
 
  protected:
   ~InputImeSendKeyEventsFunction() override {}
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 };
 
diff --git a/chrome/browser/extensions/api/input_ime/input_ime_api_chromeos.h b/chrome/browser/extensions/api/input_ime/input_ime_api_chromeos.h
index 20a1830..c07e7259 100644
--- a/chrome/browser/extensions/api/input_ime/input_ime_api_chromeos.h
+++ b/chrome/browser/extensions/api/input_ime/input_ime_api_chromeos.h
@@ -21,7 +21,7 @@
 
 namespace extensions {
 
-class InputImeClearCompositionFunction : public UIThreadExtensionFunction {
+class InputImeClearCompositionFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.clearComposition",
                              INPUT_IME_CLEARCOMPOSITION)
@@ -33,8 +33,7 @@
   ResponseAction Run() override;
 };
 
-class InputImeSetCandidateWindowPropertiesFunction
-    : public UIThreadExtensionFunction {
+class InputImeSetCandidateWindowPropertiesFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.setCandidateWindowProperties",
                              INPUT_IME_SETCANDIDATEWINDOWPROPERTIES)
@@ -46,7 +45,7 @@
   ResponseAction Run() override;
 };
 
-class InputImeSetCandidatesFunction : public UIThreadExtensionFunction {
+class InputImeSetCandidatesFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.setCandidates", INPUT_IME_SETCANDIDATES)
 
@@ -57,7 +56,7 @@
   ResponseAction Run() override;
 };
 
-class InputImeSetCursorPositionFunction : public UIThreadExtensionFunction {
+class InputImeSetCursorPositionFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.setCursorPosition",
                              INPUT_IME_SETCURSORPOSITION)
@@ -69,7 +68,7 @@
   ResponseAction Run() override;
 };
 
-class InputImeSetMenuItemsFunction : public UIThreadExtensionFunction {
+class InputImeSetMenuItemsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.setMenuItems", INPUT_IME_SETMENUITEMS)
 
@@ -80,7 +79,7 @@
   ResponseAction Run() override;
 };
 
-class InputImeUpdateMenuItemsFunction : public UIThreadExtensionFunction {
+class InputImeUpdateMenuItemsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.updateMenuItems",
                              INPUT_IME_UPDATEMENUITEMS)
@@ -92,7 +91,7 @@
   ResponseAction Run() override;
 };
 
-class InputImeDeleteSurroundingTextFunction : public UIThreadExtensionFunction {
+class InputImeDeleteSurroundingTextFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.deleteSurroundingText",
                              INPUT_IME_DELETESURROUNDINGTEXT)
@@ -103,7 +102,7 @@
   ResponseAction Run() override;
 };
 
-class InputImeHideInputViewFunction : public UIThreadExtensionFunction {
+class InputImeHideInputViewFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.hideInputView",
                              INPUT_IME_HIDEINPUTVIEW)
@@ -111,19 +110,19 @@
  protected:
   ~InputImeHideInputViewFunction() override {}
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 };
 
 class InputMethodPrivateNotifyImeMenuItemActivatedFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   InputMethodPrivateNotifyImeMenuItemActivatedFunction() {}
 
  protected:
   ~InputMethodPrivateNotifyImeMenuItemActivatedFunction() override {}
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
@@ -134,7 +133,7 @@
 };
 
 class InputMethodPrivateGetCompositionBoundsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("inputMethodPrivate.getCompositionBounds",
                              INPUTMETHODPRIVATE_GETCOMPOSITIONBOUNDS)
diff --git a/chrome/browser/extensions/api/input_ime/input_ime_api_nonchromeos.h b/chrome/browser/extensions/api/input_ime/input_ime_api_nonchromeos.h
index 84f39eb..68e06c5 100644
--- a/chrome/browser/extensions/api/input_ime/input_ime_api_nonchromeos.h
+++ b/chrome/browser/extensions/api/input_ime/input_ime_api_nonchromeos.h
@@ -55,7 +55,7 @@
   DISALLOW_COPY_AND_ASSIGN(InputImeEventRouter);
 };
 
-class InputImeCreateWindowFunction : public UIThreadExtensionFunction {
+class InputImeCreateWindowFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.createWindow", INPUT_IME_CREATEWINDOW)
 
@@ -66,7 +66,7 @@
   ExtensionFunction::ResponseAction Run() override;
 };
 
-class InputImeShowWindowFunction : public UIThreadExtensionFunction {
+class InputImeShowWindowFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.showWindow", INPUT_IME_SHOWWINDOW)
 
@@ -77,7 +77,7 @@
   ExtensionFunction::ResponseAction Run() override;
 };
 
-class InputImeHideWindowFunction : public UIThreadExtensionFunction {
+class InputImeHideWindowFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.hideWindow", INPUT_IME_HIDEWINDOW)
 
@@ -88,7 +88,7 @@
   ExtensionFunction::ResponseAction Run() override;
 };
 
-class InputImeActivateFunction : public UIThreadExtensionFunction {
+class InputImeActivateFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.activate", INPUT_IME_ACTIVATE)
 
@@ -99,7 +99,7 @@
  protected:
   ~InputImeActivateFunction() override {}
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 
  private:
@@ -109,14 +109,14 @@
   void OnPermissionBubbleFinished(ImeWarningBubblePermissionStatus status);
 };
 
-class InputImeDeactivateFunction : public UIThreadExtensionFunction {
+class InputImeDeactivateFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("input.ime.deactivate", INPUT_IME_DEACTIVATE)
 
  protected:
   ~InputImeDeactivateFunction() override {}
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ResponseAction Run() override;
 };
 
diff --git a/chrome/browser/extensions/api/instance_id/instance_id_api.h b/chrome/browser/extensions/api/instance_id/instance_id_api.h
index ffd49612..33a0bb0 100644
--- a/chrome/browser/extensions/api/instance_id/instance_id_api.h
+++ b/chrome/browser/extensions/api/instance_id/instance_id_api.h
@@ -11,7 +11,7 @@
 
 namespace extensions {
 
-class InstanceIDApiFunction : public UIThreadExtensionFunction {
+class InstanceIDApiFunction : public ExtensionFunction {
  public:
   InstanceIDApiFunction();
 
diff --git a/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.h b/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.h
index 951f544..2e745eb 100644
--- a/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.h
+++ b/chrome/browser/extensions/api/language_settings_private/language_settings_private_api.h
@@ -14,7 +14,7 @@
 
 // Implements the languageSettingsPrivate.getLanguageList method.
 class LanguageSettingsPrivateGetLanguageListFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   LanguageSettingsPrivateGetLanguageListFunction();
   DECLARE_EXTENSION_FUNCTION("languageSettingsPrivate.getLanguageList",
@@ -33,8 +33,7 @@
 };
 
 // Implements the languageSettingsPrivate.enableLanguage method.
-class LanguageSettingsPrivateEnableLanguageFunction
-    : public UIThreadExtensionFunction {
+class LanguageSettingsPrivateEnableLanguageFunction : public ExtensionFunction {
  public:
   LanguageSettingsPrivateEnableLanguageFunction();
   DECLARE_EXTENSION_FUNCTION("languageSettingsPrivate.enableLanguage",
@@ -54,7 +53,7 @@
 
 // Implements the languageSettingsPrivate.disableLanguage method.
 class LanguageSettingsPrivateDisableLanguageFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   LanguageSettingsPrivateDisableLanguageFunction();
   DECLARE_EXTENSION_FUNCTION("languageSettingsPrivate.disableLanguage",
@@ -75,7 +74,7 @@
 // Implements the languageSettingsPrivate.setEnableTranslationForLanguage
 // method.
 class LanguageSettingsPrivateSetEnableTranslationForLanguageFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   LanguageSettingsPrivateSetEnableTranslationForLanguageFunction();
   DECLARE_EXTENSION_FUNCTION(
@@ -95,8 +94,7 @@
 };
 
 // Implements the languageSettingsPrivate.moveLanguage method.
-class LanguageSettingsPrivateMoveLanguageFunction
-    : public UIThreadExtensionFunction {
+class LanguageSettingsPrivateMoveLanguageFunction : public ExtensionFunction {
  public:
   LanguageSettingsPrivateMoveLanguageFunction();
   DECLARE_EXTENSION_FUNCTION("languageSettingsPrivate.moveLanguage",
@@ -116,7 +114,7 @@
 // Implements the languageSettingsPrivate.getSpellcheckDictionaryStatuses
 // method.
 class LanguageSettingsPrivateGetSpellcheckDictionaryStatusesFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   LanguageSettingsPrivateGetSpellcheckDictionaryStatusesFunction();
   DECLARE_EXTENSION_FUNCTION(
@@ -136,7 +134,7 @@
 
 // Implements the languageSettingsPrivate.getSpellcheckWords method.
 class LanguageSettingsPrivateGetSpellcheckWordsFunction
-    : public UIThreadExtensionFunction,
+    : public ExtensionFunction,
       public SpellcheckCustomDictionary::Observer {
  public:
   LanguageSettingsPrivateGetSpellcheckWordsFunction();
@@ -163,7 +161,7 @@
 
 // Implements the languageSettingsPrivate.addSpellcheckWord method.
 class LanguageSettingsPrivateAddSpellcheckWordFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   LanguageSettingsPrivateAddSpellcheckWordFunction();
   DECLARE_EXTENSION_FUNCTION("languageSettingsPrivate.addSpellcheckWord",
@@ -181,7 +179,7 @@
 
 // Implements the languageSettingsPrivate.removeSpellcheckWord method.
 class LanguageSettingsPrivateRemoveSpellcheckWordFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   LanguageSettingsPrivateRemoveSpellcheckWordFunction();
   DECLARE_EXTENSION_FUNCTION("languageSettingsPrivate.removeSpellcheckWord",
@@ -199,7 +197,7 @@
 
 // Implements the languageSettingsPrivate.getTranslateTargetLanguage method.
 class LanguageSettingsPrivateGetTranslateTargetLanguageFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   LanguageSettingsPrivateGetTranslateTargetLanguageFunction();
   DECLARE_EXTENSION_FUNCTION(
@@ -221,7 +219,7 @@
 
 // Implements the languageSettingsPrivate.getInputMethodLists method.
 class LanguageSettingsPrivateGetInputMethodListsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   LanguageSettingsPrivateGetInputMethodListsFunction();
   DECLARE_EXTENSION_FUNCTION("languageSettingsPrivate.getInputMethodLists",
@@ -238,8 +236,7 @@
 };
 
 // Implements the languageSettingsPrivate.addInputMethod method.
-class LanguageSettingsPrivateAddInputMethodFunction
-    : public UIThreadExtensionFunction {
+class LanguageSettingsPrivateAddInputMethodFunction : public ExtensionFunction {
  public:
   LanguageSettingsPrivateAddInputMethodFunction();
   DECLARE_EXTENSION_FUNCTION("languageSettingsPrivate.addInputMethod",
@@ -259,7 +256,7 @@
 
 // Implements the languageSettingsPrivate.removeInputMethod method.
 class LanguageSettingsPrivateRemoveInputMethodFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   LanguageSettingsPrivateRemoveInputMethodFunction();
   DECLARE_EXTENSION_FUNCTION("languageSettingsPrivate.removeInputMethod",
@@ -279,7 +276,7 @@
 
 // Implements the languageSettingsPrivate.retryDownloadDictionary method.
 class LanguageSettingsPrivateRetryDownloadDictionaryFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   LanguageSettingsPrivateRetryDownloadDictionaryFunction();
   DECLARE_EXTENSION_FUNCTION("languageSettingsPrivate.retryDownloadDictionary",
diff --git a/chrome/browser/extensions/api/management/management_api_unittest.cc b/chrome/browser/extensions/api/management/management_api_unittest.cc
index 9b7ea704..aa72733 100644
--- a/chrome/browser/extensions/api/management/management_api_unittest.cc
+++ b/chrome/browser/extensions/api/management/management_api_unittest.cc
@@ -62,7 +62,7 @@
 
   // A wrapper around extension_function_test_utils::RunFunction that runs with
   // the associated browser, no flags, and can take stack-allocated arguments.
-  bool RunFunction(const scoped_refptr<UIThreadExtensionFunction>& function,
+  bool RunFunction(const scoped_refptr<ExtensionFunction>& function,
                    const base::ListValue& args);
 
   Browser* browser() { return browser_.get(); }
@@ -80,7 +80,7 @@
 };
 
 bool ManagementApiUnitTest::RunFunction(
-    const scoped_refptr<UIThreadExtensionFunction>& function,
+    const scoped_refptr<ExtensionFunction>& function,
     const base::ListValue& args) {
   return extension_function_test_utils::RunFunction(
       function.get(), base::WrapUnique(args.DeepCopy()), browser(),
@@ -271,7 +271,7 @@
         ScopedTestDialogAutoConfirm::ACCEPT);
 
     // Uninstall requires a user gesture, so this should fail.
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new ManagementUninstallFunction());
     EXPECT_FALSE(RunFunction(function, uninstall_args));
     EXPECT_EQ(std::string(constants::kGestureNeededForUninstallError),
@@ -295,7 +295,7 @@
     ExtensionFunction::ScopedUserGestureForTests scoped_user_gesture;
 
     service()->AddExtension(extension.get());
-    scoped_refptr<UIThreadExtensionFunction> function =
+    scoped_refptr<ExtensionFunction> function =
         new ManagementUninstallFunction();
     EXPECT_TRUE(registry()->enabled_extensions().Contains(extension_id));
     EXPECT_FALSE(RunFunction(function, uninstall_args));
@@ -347,7 +347,7 @@
         ScopedTestDialogAutoConfirm::CANCEL);
     ExtensionFunction::ScopedUserGestureForTests scoped_user_gesture;
 
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new ManagementUninstallFunction());
     function->set_extension(triggering_extension);
     EXPECT_TRUE(registry()->enabled_extensions().Contains(extension_id));
@@ -360,7 +360,7 @@
   }
 
   {
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new ManagementUninstallFunction());
     function->set_extension(triggering_extension);
 
@@ -397,7 +397,7 @@
   base::ListValue uninstall_args;
   uninstall_args.AppendString(extension->id());
   {
-    scoped_refptr<UIThreadExtensionFunction> function(
+    scoped_refptr<ExtensionFunction> function(
         new ManagementUninstallFunction());
     function->set_extension(triggering_extension);
 
@@ -435,8 +435,7 @@
 
   ScopedTestDialogAutoConfirm auto_confirm(ScopedTestDialogAutoConfirm::ACCEPT);
   ExtensionFunction::ScopedUserGestureForTests scoped_user_gesture;
-  scoped_refptr<UIThreadExtensionFunction> function(
-      new ManagementUninstallFunction());
+  scoped_refptr<ExtensionFunction> function(new ManagementUninstallFunction());
   base::ListValue uninstall_args;
   uninstall_args.AppendString(id);
   EXPECT_TRUE(RunFunction(function, uninstall_args)) << function->GetError();
@@ -452,7 +451,7 @@
   service()->BlacklistExtensionForTest(id);
   EXPECT_NE(nullptr, registry()->GetInstalledExtension(id));
 
-  scoped_refptr<UIThreadExtensionFunction> function;
+  scoped_refptr<ExtensionFunction> function;
 
   // Test enabling it.
   {
@@ -486,7 +485,7 @@
 
   const std::string args =
       base::StringPrintf("[\"%s\"]", extension->id().c_str());
-  scoped_refptr<UIThreadExtensionFunction> function;
+  scoped_refptr<ExtensionFunction> function;
 
   // Initially the extension should show as enabled.
   EXPECT_TRUE(registry()->enabled_extensions().Contains(extension->id()));
diff --git a/chrome/browser/extensions/api/mdns/mdns_api.h b/chrome/browser/extensions/api/mdns/mdns_api.h
index 19464a2e..dbfe3b4 100644
--- a/chrome/browser/extensions/api/mdns/mdns_api.h
+++ b/chrome/browser/extensions/api/mdns/mdns_api.h
@@ -118,7 +118,7 @@
   DISALLOW_COPY_AND_ASSIGN(MDnsAPI);
 };
 
-class MdnsForceDiscoveryFunction : public UIThreadExtensionFunction {
+class MdnsForceDiscoveryFunction : public ExtensionFunction {
  public:
   MdnsForceDiscoveryFunction();
 
@@ -126,7 +126,7 @@
   ~MdnsForceDiscoveryFunction() override;
 
  private:
-  // UIThreadExtensionFunction override.
+  // ExtensionFunction override.
   ResponseAction Run() override;
 
   DECLARE_EXTENSION_FUNCTION("mdns.forceDiscovery", MDNS_FORCEDISCOVERY)
diff --git a/chrome/browser/extensions/api/module/module.h b/chrome/browser/extensions/api/module/module.h
index de81de0d..cbdde20 100644
--- a/chrome/browser/extensions/api/module/module.h
+++ b/chrome/browser/extensions/api/module/module.h
@@ -16,7 +16,7 @@
                              const std::string& extension_id);
 }  // namespace extension
 
-class ExtensionSetUpdateUrlDataFunction : public UIThreadExtensionFunction {
+class ExtensionSetUpdateUrlDataFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("extension.setUpdateUrlData",
                              EXTENSION_SETUPDATEURLDATA)
@@ -28,8 +28,7 @@
   ResponseAction Run() override;
 };
 
-class ExtensionIsAllowedIncognitoAccessFunction
-    : public UIThreadExtensionFunction {
+class ExtensionIsAllowedIncognitoAccessFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("extension.isAllowedIncognitoAccess",
                              EXTENSION_ISALLOWEDINCOGNITOACCESS)
@@ -41,8 +40,7 @@
   ResponseAction Run() override;
 };
 
-class ExtensionIsAllowedFileSchemeAccessFunction
-    : public UIThreadExtensionFunction {
+class ExtensionIsAllowedFileSchemeAccessFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("extension.isAllowedFileSchemeAccess",
                              EXTENSION_ISALLOWEDFILESCHEMEACCESS)
diff --git a/chrome/browser/extensions/api/networking_cast_private/networking_cast_private_api.h b/chrome/browser/extensions/api/networking_cast_private/networking_cast_private_api.h
index 4f12d14..daf23fba 100644
--- a/chrome/browser/extensions/api/networking_cast_private/networking_cast_private_api.h
+++ b/chrome/browser/extensions/api/networking_cast_private/networking_cast_private_api.h
@@ -18,7 +18,7 @@
 namespace extensions {
 
 class NetworkingCastPrivateVerifyDestinationFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   NetworkingCastPrivateVerifyDestinationFunction() {}
   DECLARE_EXTENSION_FUNCTION("networking.castPrivate.verifyDestination",
@@ -38,7 +38,7 @@
 };
 
 class NetworkingCastPrivateVerifyAndEncryptDataFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   NetworkingCastPrivateVerifyAndEncryptDataFunction() {}
   DECLARE_EXTENSION_FUNCTION("networking.castPrivate.verifyAndEncryptData",
@@ -58,7 +58,7 @@
 };
 
 class NetworkingCastPrivateSetWifiTDLSEnabledStateFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   NetworkingCastPrivateSetWifiTDLSEnabledStateFunction() {}
   DECLARE_EXTENSION_FUNCTION("networking.castPrivate.setWifiTDLSEnabledState",
@@ -82,7 +82,7 @@
 };
 
 class NetworkingCastPrivateGetWifiTDLSStatusFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   NetworkingCastPrivateGetWifiTDLSStatusFunction() {}
   DECLARE_EXTENSION_FUNCTION("networking.castPrivate.getWifiTDLSStatus",
diff --git a/chrome/browser/extensions/api/omnibox/omnibox_api.h b/chrome/browser/extensions/api/omnibox/omnibox_api.h
index 27c7981..435ea64 100644
--- a/chrome/browser/extensions/api/omnibox/omnibox_api.h
+++ b/chrome/browser/extensions/api/omnibox/omnibox_api.h
@@ -74,7 +74,7 @@
   DISALLOW_COPY_AND_ASSIGN(ExtensionOmniboxEventRouter);
 };
 
-class OmniboxSendSuggestionsFunction : public UIThreadExtensionFunction {
+class OmniboxSendSuggestionsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("omnibox.sendSuggestions", OMNIBOX_SENDSUGGESTIONS)
 
@@ -147,7 +147,7 @@
 template <>
 void BrowserContextKeyedAPIFactory<OmniboxAPI>::DeclareFactoryDependencies();
 
-class OmniboxSetDefaultSuggestionFunction : public UIThreadExtensionFunction {
+class OmniboxSetDefaultSuggestionFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("omnibox.setDefaultSuggestion",
                              OMNIBOX_SETDEFAULTSUGGESTION)
diff --git a/chrome/browser/extensions/api/passwords_private/passwords_private_api.h b/chrome/browser/extensions/api/passwords_private/passwords_private_api.h
index 5b94478..b9521497 100644
--- a/chrome/browser/extensions/api/passwords_private/passwords_private_api.h
+++ b/chrome/browser/extensions/api/passwords_private/passwords_private_api.h
@@ -17,7 +17,7 @@
 namespace extensions {
 
 class PasswordsPrivateRecordPasswordsPageAccessInSettingsFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   PasswordsPrivateRecordPasswordsPageAccessInSettingsFunction() {}
   DECLARE_EXTENSION_FUNCTION(
@@ -35,8 +35,7 @@
       PasswordsPrivateRecordPasswordsPageAccessInSettingsFunction);
 };
 
-class PasswordsPrivateChangeSavedPasswordFunction
-    : public UIThreadExtensionFunction {
+class PasswordsPrivateChangeSavedPasswordFunction : public ExtensionFunction {
  public:
   PasswordsPrivateChangeSavedPasswordFunction() {}
   DECLARE_EXTENSION_FUNCTION("passwordsPrivate.changeSavedPassword",
@@ -52,8 +51,7 @@
   DISALLOW_COPY_AND_ASSIGN(PasswordsPrivateChangeSavedPasswordFunction);
 };
 
-class PasswordsPrivateRemoveSavedPasswordFunction :
-    public UIThreadExtensionFunction {
+class PasswordsPrivateRemoveSavedPasswordFunction : public ExtensionFunction {
  public:
   PasswordsPrivateRemoveSavedPasswordFunction() {}
   DECLARE_EXTENSION_FUNCTION("passwordsPrivate.removeSavedPassword",
@@ -69,8 +67,8 @@
   DISALLOW_COPY_AND_ASSIGN(PasswordsPrivateRemoveSavedPasswordFunction);
 };
 
-class PasswordsPrivateRemovePasswordExceptionFunction :
-    public UIThreadExtensionFunction {
+class PasswordsPrivateRemovePasswordExceptionFunction
+    : public ExtensionFunction {
  public:
   PasswordsPrivateRemovePasswordExceptionFunction() {}
   DECLARE_EXTENSION_FUNCTION("passwordsPrivate.removePasswordException",
@@ -87,7 +85,7 @@
 };
 
 class PasswordsPrivateUndoRemoveSavedPasswordOrExceptionFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   PasswordsPrivateUndoRemoveSavedPasswordOrExceptionFunction() {}
   DECLARE_EXTENSION_FUNCTION(
@@ -105,8 +103,8 @@
       PasswordsPrivateUndoRemoveSavedPasswordOrExceptionFunction);
 };
 
-class PasswordsPrivateRequestPlaintextPasswordFunction :
-    public UIThreadExtensionFunction {
+class PasswordsPrivateRequestPlaintextPasswordFunction
+    : public ExtensionFunction {
  public:
   PasswordsPrivateRequestPlaintextPasswordFunction() {}
   DECLARE_EXTENSION_FUNCTION("passwordsPrivate.requestPlaintextPassword",
@@ -124,8 +122,7 @@
   DISALLOW_COPY_AND_ASSIGN(PasswordsPrivateRequestPlaintextPasswordFunction);
 };
 
-class PasswordsPrivateGetSavedPasswordListFunction
-    : public UIThreadExtensionFunction {
+class PasswordsPrivateGetSavedPasswordListFunction : public ExtensionFunction {
  public:
   PasswordsPrivateGetSavedPasswordListFunction() {}
   DECLARE_EXTENSION_FUNCTION("passwordsPrivate.getSavedPasswordList",
@@ -145,7 +142,7 @@
 };
 
 class PasswordsPrivateGetPasswordExceptionListFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   PasswordsPrivateGetPasswordExceptionListFunction() {}
   DECLARE_EXTENSION_FUNCTION("passwordsPrivate.getPasswordExceptionList",
@@ -164,8 +161,7 @@
   DISALLOW_COPY_AND_ASSIGN(PasswordsPrivateGetPasswordExceptionListFunction);
 };
 
-class PasswordsPrivateImportPasswordsFunction
-    : public UIThreadExtensionFunction {
+class PasswordsPrivateImportPasswordsFunction : public ExtensionFunction {
  public:
   PasswordsPrivateImportPasswordsFunction() {}
   DECLARE_EXTENSION_FUNCTION("passwordsPrivate.importPasswords",
@@ -181,8 +177,7 @@
   DISALLOW_COPY_AND_ASSIGN(PasswordsPrivateImportPasswordsFunction);
 };
 
-class PasswordsPrivateExportPasswordsFunction
-    : public UIThreadExtensionFunction {
+class PasswordsPrivateExportPasswordsFunction : public ExtensionFunction {
  public:
   PasswordsPrivateExportPasswordsFunction() {}
   DECLARE_EXTENSION_FUNCTION("passwordsPrivate.exportPasswords",
@@ -200,8 +195,7 @@
   DISALLOW_COPY_AND_ASSIGN(PasswordsPrivateExportPasswordsFunction);
 };
 
-class PasswordsPrivateCancelExportPasswordsFunction
-    : public UIThreadExtensionFunction {
+class PasswordsPrivateCancelExportPasswordsFunction : public ExtensionFunction {
  public:
   PasswordsPrivateCancelExportPasswordsFunction() {}
   DECLARE_EXTENSION_FUNCTION("passwordsPrivate.cancelExportPasswords",
@@ -218,7 +212,7 @@
 };
 
 class PasswordsPrivateRequestExportProgressStatusFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   PasswordsPrivateRequestExportProgressStatusFunction() {}
   DECLARE_EXTENSION_FUNCTION("passwordsPrivate.requestExportProgressStatus",
diff --git a/chrome/browser/extensions/api/permissions/permissions_api.h b/chrome/browser/extensions/api/permissions/permissions_api.h
index 87c04d9..e25d14c 100644
--- a/chrome/browser/extensions/api/permissions/permissions_api.h
+++ b/chrome/browser/extensions/api/permissions/permissions_api.h
@@ -16,7 +16,7 @@
 namespace extensions {
 
 // chrome.permissions.contains
-class PermissionsContainsFunction : public UIThreadExtensionFunction {
+class PermissionsContainsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("permissions.contains", PERMISSIONS_CONTAINS)
 
@@ -28,7 +28,7 @@
 };
 
 // chrome.permissions.getAll
-class PermissionsGetAllFunction : public UIThreadExtensionFunction {
+class PermissionsGetAllFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("permissions.getAll", PERMISSIONS_GETALL)
 
@@ -40,7 +40,7 @@
 };
 
 // chrome.permissions.remove
-class PermissionsRemoveFunction : public UIThreadExtensionFunction {
+class PermissionsRemoveFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("permissions.remove", PERMISSIONS_REMOVE)
 
@@ -52,7 +52,7 @@
 };
 
 // chrome.permissions.request
-class PermissionsRequestFunction : public UIThreadExtensionFunction {
+class PermissionsRequestFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("permissions.request", PERMISSIONS_REQUEST)
 
diff --git a/chrome/browser/extensions/api/platform_keys/platform_keys_api.h b/chrome/browser/extensions/api/platform_keys/platform_keys_api.h
index b632e4e..4d1ece03 100644
--- a/chrome/browser/extensions/api/platform_keys/platform_keys_api.h
+++ b/chrome/browser/extensions/api/platform_keys/platform_keys_api.h
@@ -33,7 +33,7 @@
 }  // namespace platform_keys
 
 class PlatformKeysInternalSelectClientCertificatesFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  private:
   ~PlatformKeysInternalSelectClientCertificatesFunction() override;
   ResponseAction Run() override;
@@ -47,8 +47,7 @@
                              PLATFORMKEYSINTERNAL_SELECTCLIENTCERTIFICATES)
 };
 
-class PlatformKeysInternalGetPublicKeyFunction
-    : public UIThreadExtensionFunction {
+class PlatformKeysInternalGetPublicKeyFunction : public ExtensionFunction {
  private:
   ~PlatformKeysInternalGetPublicKeyFunction() override;
   ResponseAction Run() override;
@@ -57,7 +56,7 @@
                              PLATFORMKEYSINTERNAL_GETPUBLICKEY)
 };
 
-class PlatformKeysInternalSignFunction : public UIThreadExtensionFunction {
+class PlatformKeysInternalSignFunction : public ExtensionFunction {
  private:
   ~PlatformKeysInternalSignFunction() override;
   ResponseAction Run() override;
@@ -71,7 +70,7 @@
 };
 
 class PlatformKeysVerifyTLSServerCertificateFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  private:
   ~PlatformKeysVerifyTLSServerCertificateFunction() override;
   ResponseAction Run() override;
diff --git a/chrome/browser/extensions/api/preference/preference_api.h b/chrome/browser/extensions/api/preference/preference_api.h
index 80d27cc..086434a 100644
--- a/chrome/browser/extensions/api/preference/preference_api.h
+++ b/chrome/browser/extensions/api/preference/preference_api.h
@@ -175,7 +175,7 @@
 
 // A base class to provide functionality common to the other *PreferenceFunction
 // classes.
-class PreferenceFunction : public UIThreadExtensionFunction {
+class PreferenceFunction : public ExtensionFunction {
  protected:
   enum PermissionType { PERMISSION_TYPE_READ, PERMISSION_TYPE_WRITE };
 
diff --git a/chrome/browser/extensions/api/processes/processes_api.h b/chrome/browser/extensions/api/processes/processes_api.h
index f1ef0d68..f72d0525 100644
--- a/chrome/browser/extensions/api/processes/processes_api.h
+++ b/chrome/browser/extensions/api/processes/processes_api.h
@@ -110,9 +110,9 @@
 ////////////////////////////////////////////////////////////////////////////////
 // This extension function returns the Process object for the renderer process
 // currently in use by the specified Tab.
-class ProcessesGetProcessIdForTabFunction : public UIThreadExtensionFunction {
+class ProcessesGetProcessIdForTabFunction : public ExtensionFunction {
  public:
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ExtensionFunction::ResponseAction Run() override;
 
   DECLARE_EXTENSION_FUNCTION("processes.getProcessIdForTab",
@@ -128,9 +128,9 @@
 // Using unique IDs instead of OS process IDs allows two advantages:
 // * guaranteed uniqueness, since OS process IDs can be reused.
 // * guards against killing non-Chrome processes.
-class ProcessesTerminateFunction : public UIThreadExtensionFunction {
+class ProcessesTerminateFunction : public ExtensionFunction {
  public:
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ExtensionFunction::ResponseAction Run() override;
 
   DECLARE_EXTENSION_FUNCTION("processes.terminate", PROCESSES_TERMINATE)
@@ -157,13 +157,13 @@
 ////////////////////////////////////////////////////////////////////////////////
 // Extension function which returns a set of Process objects, containing the
 // details corresponding to the process IDs supplied as input.
-class ProcessesGetProcessInfoFunction :
-    public UIThreadExtensionFunction,
-    public task_manager::TaskManagerObserver {
+class ProcessesGetProcessInfoFunction
+    : public ExtensionFunction,
+      public task_manager::TaskManagerObserver {
  public:
   ProcessesGetProcessInfoFunction();
 
-  // UIThreadExtensionFunction:
+  // ExtensionFunction:
   ExtensionFunction::ResponseAction Run() override;
 
   // task_manager::TaskManagerObserver:
diff --git a/chrome/browser/extensions/api/resources_private/resources_private_api.h b/chrome/browser/extensions/api/resources_private/resources_private_api.h
index ce37f9dc..4440d65 100644
--- a/chrome/browser/extensions/api/resources_private/resources_private_api.h
+++ b/chrome/browser/extensions/api/resources_private/resources_private_api.h
@@ -10,7 +10,7 @@
 
 namespace extensions {
 
-class ResourcesPrivateGetStringsFunction : public UIThreadExtensionFunction {
+class ResourcesPrivateGetStringsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("resourcesPrivate.getStrings",
                              RESOURCESPRIVATE_GETSTRINGS)
diff --git a/chrome/browser/extensions/api/safe_browsing_private/safe_browsing_private_api.h b/chrome/browser/extensions/api/safe_browsing_private/safe_browsing_private_api.h
index d28ce05..13980a7 100644
--- a/chrome/browser/extensions/api/safe_browsing_private/safe_browsing_private_api.h
+++ b/chrome/browser/extensions/api/safe_browsing_private/safe_browsing_private_api.h
@@ -9,8 +9,7 @@
 
 namespace extensions {
 
-class SafeBrowsingPrivateGetReferrerChainFunction
-    : public UIThreadExtensionFunction {
+class SafeBrowsingPrivateGetReferrerChainFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("safeBrowsingPrivate.getReferrerChain",
                              SAFEBROWSINGPRIVATE_GETREFERRERCHAIN)
diff --git a/chrome/browser/extensions/api/sessions/sessions_api.h b/chrome/browser/extensions/api/sessions/sessions_api.h
index d859f64..6d177c1 100644
--- a/chrome/browser/extensions/api/sessions/sessions_api.h
+++ b/chrome/browser/extensions/api/sessions/sessions_api.h
@@ -27,7 +27,7 @@
 
 class SessionId;
 
-class SessionsGetRecentlyClosedFunction : public UIThreadExtensionFunction {
+class SessionsGetRecentlyClosedFunction : public ExtensionFunction {
  protected:
   ~SessionsGetRecentlyClosedFunction() override {}
   ResponseAction Run() override;
@@ -43,7 +43,7 @@
       const sessions::TabRestoreService::Entry& entry);
 };
 
-class SessionsGetDevicesFunction : public UIThreadExtensionFunction {
+class SessionsGetDevicesFunction : public ExtensionFunction {
  protected:
   ~SessionsGetDevicesFunction() override {}
   ResponseAction Run() override;
@@ -64,7 +64,7 @@
       const sync_sessions::SyncedSession* session);
 };
 
-class SessionsRestoreFunction : public UIThreadExtensionFunction {
+class SessionsRestoreFunction : public ExtensionFunction {
  protected:
   ~SessionsRestoreFunction() override {}
   ResponseAction Run() override;
diff --git a/chrome/browser/extensions/api/settings_private/settings_private_api.h b/chrome/browser/extensions/api/settings_private/settings_private_api.h
index f9a377d..ec333f2 100644
--- a/chrome/browser/extensions/api/settings_private/settings_private_api.h
+++ b/chrome/browser/extensions/api/settings_private/settings_private_api.h
@@ -13,7 +13,7 @@
 namespace extensions {
 
 // Implements the chrome.settingsPrivate.setPref method.
-class SettingsPrivateSetPrefFunction : public UIThreadExtensionFunction {
+class SettingsPrivateSetPrefFunction : public ExtensionFunction {
  public:
   SettingsPrivateSetPrefFunction() {}
   DECLARE_EXTENSION_FUNCTION("settingsPrivate.setPref", SETTINGSPRIVATE_SETPREF)
@@ -21,14 +21,14 @@
  protected:
   ~SettingsPrivateSetPrefFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
   DISALLOW_COPY_AND_ASSIGN(SettingsPrivateSetPrefFunction);
 };
 
 // Implements the chrome.settingsPrivate.getAllPrefs method.
-class SettingsPrivateGetAllPrefsFunction : public UIThreadExtensionFunction {
+class SettingsPrivateGetAllPrefsFunction : public ExtensionFunction {
  public:
   SettingsPrivateGetAllPrefsFunction() {}
   DECLARE_EXTENSION_FUNCTION("settingsPrivate.getAllPrefs",
@@ -37,14 +37,14 @@
  protected:
   ~SettingsPrivateGetAllPrefsFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
   DISALLOW_COPY_AND_ASSIGN(SettingsPrivateGetAllPrefsFunction);
 };
 
 // Implements the chrome.settingsPrivate.getPref method.
-class SettingsPrivateGetPrefFunction : public UIThreadExtensionFunction {
+class SettingsPrivateGetPrefFunction : public ExtensionFunction {
  public:
   SettingsPrivateGetPrefFunction() {}
   DECLARE_EXTENSION_FUNCTION("settingsPrivate.getPref", SETTINGSPRIVATE_GETPREF)
@@ -52,15 +52,14 @@
  protected:
   ~SettingsPrivateGetPrefFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
   DISALLOW_COPY_AND_ASSIGN(SettingsPrivateGetPrefFunction);
 };
 
 // Implements the chrome.settingsPrivate.getDefaultZoom method.
-class SettingsPrivateGetDefaultZoomFunction
-    : public UIThreadExtensionFunction {
+class SettingsPrivateGetDefaultZoomFunction : public ExtensionFunction {
  public:
   SettingsPrivateGetDefaultZoomFunction() {}
   DECLARE_EXTENSION_FUNCTION("settingsPrivate.getDefaultZoom",
@@ -69,15 +68,14 @@
  protected:
   ~SettingsPrivateGetDefaultZoomFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
   DISALLOW_COPY_AND_ASSIGN(SettingsPrivateGetDefaultZoomFunction);
 };
 
 // Implements the chrome.settingsPrivate.setDefaultZoom method.
-class SettingsPrivateSetDefaultZoomFunction
-    : public UIThreadExtensionFunction {
+class SettingsPrivateSetDefaultZoomFunction : public ExtensionFunction {
  public:
   SettingsPrivateSetDefaultZoomFunction() {}
   DECLARE_EXTENSION_FUNCTION("settingsPrivate.setDefaultZoom",
@@ -86,7 +84,7 @@
  protected:
   ~SettingsPrivateSetDefaultZoomFunction() override;
 
-  // UIThreadExtensionFunction overrides.
+  // ExtensionFunction overrides.
   ResponseAction Run() override;
 
   DISALLOW_COPY_AND_ASSIGN(SettingsPrivateSetDefaultZoomFunction);
diff --git a/chrome/browser/extensions/api/signed_in_devices/signed_in_devices_api.h b/chrome/browser/extensions/api/signed_in_devices/signed_in_devices_api.h
index b24066b..c46442ec 100644
--- a/chrome/browser/extensions/api/signed_in_devices/signed_in_devices_api.h
+++ b/chrome/browser/extensions/api/signed_in_devices/signed_in_devices_api.h
@@ -37,7 +37,7 @@
     syncer::DeviceInfoTracker* device_tracker,
     ExtensionPrefs* extension_prefs);
 
-class SignedInDevicesGetFunction : public UIThreadExtensionFunction {
+class SignedInDevicesGetFunction : public ExtensionFunction {
  protected:
   ~SignedInDevicesGetFunction() override {}
 
diff --git a/chrome/browser/extensions/api/system_indicator/system_indicator_api.h b/chrome/browser/extensions/api/system_indicator/system_indicator_api.h
index b0bd25e..5b3ca7b 100644
--- a/chrome/browser/extensions/api/system_indicator/system_indicator_api.h
+++ b/chrome/browser/extensions/api/system_indicator/system_indicator_api.h
@@ -9,7 +9,7 @@
 
 namespace extensions {
 
-class SystemIndicatorSetIconFunction : public UIThreadExtensionFunction {
+class SystemIndicatorSetIconFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("systemIndicator.setIcon", SYSTEMINDICATOR_SETICON)
 
@@ -19,7 +19,7 @@
   ~SystemIndicatorSetIconFunction() override {}
 };
 
-class SystemIndicatorEnableFunction : public UIThreadExtensionFunction {
+class SystemIndicatorEnableFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("systemIndicator.enable", SYSTEMINDICATOR_ENABLE)
 
@@ -29,7 +29,7 @@
   ~SystemIndicatorEnableFunction() override {}
 };
 
-class SystemIndicatorDisableFunction : public UIThreadExtensionFunction {
+class SystemIndicatorDisableFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("systemIndicator.disable", SYSTEMINDICATOR_DISABLE)
 
diff --git a/chrome/browser/extensions/api/system_private/system_private_api.h b/chrome/browser/extensions/api/system_private/system_private_api.h
index 5d6fb2bc..9c912f0 100644
--- a/chrome/browser/extensions/api/system_private/system_private_api.h
+++ b/chrome/browser/extensions/api/system_private/system_private_api.h
@@ -13,7 +13,7 @@
 namespace extensions {
 
 class SystemPrivateGetIncognitoModeAvailabilityFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("systemPrivate.getIncognitoModeAvailability",
                              SYSTEMPRIVATE_GETINCOGNITOMODEAVAILABILITY)
@@ -26,7 +26,7 @@
 };
 
 // API function which returns the status of system update.
-class SystemPrivateGetUpdateStatusFunction : public UIThreadExtensionFunction {
+class SystemPrivateGetUpdateStatusFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("systemPrivate.getUpdateStatus",
                              SYSTEMPRIVATE_GETUPDATESTATUS)
@@ -39,7 +39,7 @@
 };
 
 // API function which returns the Google API key.
-class SystemPrivateGetApiKeyFunction : public UIThreadExtensionFunction {
+class SystemPrivateGetApiKeyFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("systemPrivate.getApiKey", SYSTEMPRIVATE_GETAPIKEY)
 
diff --git a/chrome/browser/extensions/api/tab_capture/tab_capture_api.h b/chrome/browser/extensions/api/tab_capture/tab_capture_api.h
index 2f3979b..15c0827e 100644
--- a/chrome/browser/extensions/api/tab_capture/tab_capture_api.h
+++ b/chrome/browser/extensions/api/tab_capture/tab_capture_api.h
@@ -22,7 +22,7 @@
 // Extension ids for the chromecast.
 extern const char* const kChromecastExtensionIds[6];
 
-class TabCaptureCaptureFunction : public UIThreadExtensionFunction {
+class TabCaptureCaptureFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("tabCapture.capture", TABCAPTURE_CAPTURE)
 
@@ -33,7 +33,7 @@
   ResponseAction Run() final;
 };
 
-class TabCaptureGetCapturedTabsFunction : public UIThreadExtensionFunction {
+class TabCaptureGetCapturedTabsFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("tabCapture.getCapturedTabs",
                              TABCAPTURE_GETCAPTUREDTABS)
@@ -45,7 +45,7 @@
   ResponseAction Run() final;
 };
 
-class TabCaptureCaptureOffscreenTabFunction : public UIThreadExtensionFunction {
+class TabCaptureCaptureOffscreenTabFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("tabCapture.captureOffscreenTab",
                              TABCAPTURE_CAPTUREOFFSCREENTAB)
@@ -62,7 +62,7 @@
   ResponseAction Run() final;
 };
 
-class TabCaptureGetMediaStreamIdFunction : public UIThreadExtensionFunction {
+class TabCaptureGetMediaStreamIdFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("tabCapture.getMediaStreamId",
                              TABCAPTURE_GETMEDIASTREAMID)
diff --git a/chrome/browser/extensions/api/tabs/tabs_api.cc b/chrome/browser/extensions/api/tabs/tabs_api.cc
index 03306fa..1e8ca806 100644
--- a/chrome/browser/extensions/api/tabs/tabs_api.cc
+++ b/chrome/browser/extensions/api/tabs/tabs_api.cc
@@ -148,7 +148,7 @@
   return true;
 }
 
-bool GetBrowserFromWindowID(UIThreadExtensionFunction* function,
+bool GetBrowserFromWindowID(ExtensionFunction* function,
                             int window_id,
                             Browser** browser,
                             std::string* error) {
@@ -182,10 +182,9 @@
 // Gets the WebContents for |tab_id| if it is specified. Otherwise get the
 // WebContents for the active tab in the |function|'s current window.
 // Returns nullptr and fills |error| if failed.
-content::WebContents* GetTabsAPIDefaultWebContents(
-    UIThreadExtensionFunction* function,
-    int tab_id,
-    std::string* error) {
+content::WebContents* GetTabsAPIDefaultWebContents(ExtensionFunction* function,
+                                                   int tab_id,
+                                                   std::string* error) {
   content::WebContents* web_contents = nullptr;
   if (tab_id != -1) {
     // We assume this call leaves web_contents unchanged if it is unsuccessful.
diff --git a/chrome/browser/extensions/api/tabs/tabs_api.h b/chrome/browser/extensions/api/tabs/tabs_api.h
index 37c2da5..ed3aa53 100644
--- a/chrome/browser/extensions/api/tabs/tabs_api.h
+++ b/chrome/browser/extensions/api/tabs/tabs_api.h
@@ -44,27 +44,27 @@
                             api::tabs::ZoomSettings* zoom_settings);
 
 // Windows
-class WindowsGetFunction : public UIThreadExtensionFunction {
+class WindowsGetFunction : public ExtensionFunction {
   ~WindowsGetFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("windows.get", WINDOWS_GET)
 };
-class WindowsGetCurrentFunction : public UIThreadExtensionFunction {
+class WindowsGetCurrentFunction : public ExtensionFunction {
   ~WindowsGetCurrentFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("windows.getCurrent", WINDOWS_GETCURRENT)
 };
-class WindowsGetLastFocusedFunction : public UIThreadExtensionFunction {
+class WindowsGetLastFocusedFunction : public ExtensionFunction {
   ~WindowsGetLastFocusedFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("windows.getLastFocused", WINDOWS_GETLASTFOCUSED)
 };
-class WindowsGetAllFunction : public UIThreadExtensionFunction {
+class WindowsGetAllFunction : public ExtensionFunction {
   ~WindowsGetAllFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("windows.getAll", WINDOWS_GETALL)
 };
-class WindowsCreateFunction : public UIThreadExtensionFunction {
+class WindowsCreateFunction : public ExtensionFunction {
   ~WindowsCreateFunction() override {}
   ResponseAction Run() override;
   // Returns whether the window should be created in incognito mode.
@@ -80,54 +80,54 @@
       std::string* error);
   DECLARE_EXTENSION_FUNCTION("windows.create", WINDOWS_CREATE)
 };
-class WindowsUpdateFunction : public UIThreadExtensionFunction {
+class WindowsUpdateFunction : public ExtensionFunction {
   ~WindowsUpdateFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("windows.update", WINDOWS_UPDATE)
 };
-class WindowsRemoveFunction : public UIThreadExtensionFunction {
+class WindowsRemoveFunction : public ExtensionFunction {
   ~WindowsRemoveFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("windows.remove", WINDOWS_REMOVE)
 };
 
 // Tabs
-class TabsGetFunction : public UIThreadExtensionFunction {
+class TabsGetFunction : public ExtensionFunction {
   ~TabsGetFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tabs.get", TABS_GET)
 };
-class TabsGetCurrentFunction : public UIThreadExtensionFunction {
+class TabsGetCurrentFunction : public ExtensionFunction {
   ~TabsGetCurrentFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tabs.getCurrent", TABS_GETCURRENT)
 };
-class TabsGetSelectedFunction : public UIThreadExtensionFunction {
+class TabsGetSelectedFunction : public ExtensionFunction {
   ~TabsGetSelectedFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tabs.getSelected", TABS_GETSELECTED)
 };
-class TabsGetAllInWindowFunction : public UIThreadExtensionFunction {
+class TabsGetAllInWindowFunction : public ExtensionFunction {
   ~TabsGetAllInWindowFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tabs.getAllInWindow", TABS_GETALLINWINDOW)
 };
-class TabsQueryFunction : public UIThreadExtensionFunction {
+class TabsQueryFunction : public ExtensionFunction {
   ~TabsQueryFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tabs.query", TABS_QUERY)
 };
-class TabsCreateFunction : public UIThreadExtensionFunction {
+class TabsCreateFunction : public ExtensionFunction {
   ~TabsCreateFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tabs.create", TABS_CREATE)
 };
-class TabsDuplicateFunction : public UIThreadExtensionFunction {
+class TabsDuplicateFunction : public ExtensionFunction {
   ~TabsDuplicateFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tabs.duplicate", TABS_DUPLICATE)
 };
-class TabsHighlightFunction : public UIThreadExtensionFunction {
+class TabsHighlightFunction : public ExtensionFunction {
   ~TabsHighlightFunction() override {}
   ResponseAction Run() override;
   bool HighlightTab(TabStripModel* tabstrip,
@@ -137,7 +137,7 @@
                     std::string* error);
   DECLARE_EXTENSION_FUNCTION("tabs.highlight", TABS_HIGHLIGHT)
 };
-class TabsUpdateFunction : public UIThreadExtensionFunction {
+class TabsUpdateFunction : public ExtensionFunction {
  public:
   TabsUpdateFunction();
 
@@ -158,7 +158,7 @@
 
   DECLARE_EXTENSION_FUNCTION("tabs.update", TABS_UPDATE)
 };
-class TabsMoveFunction : public UIThreadExtensionFunction {
+class TabsMoveFunction : public ExtensionFunction {
   ~TabsMoveFunction() override {}
   ResponseAction Run() override;
   bool MoveTab(int tab_id,
@@ -169,19 +169,19 @@
                std::string* error);
   DECLARE_EXTENSION_FUNCTION("tabs.move", TABS_MOVE)
 };
-class TabsReloadFunction : public UIThreadExtensionFunction {
+class TabsReloadFunction : public ExtensionFunction {
   ~TabsReloadFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tabs.reload", TABS_RELOAD)
 };
-class TabsRemoveFunction : public UIThreadExtensionFunction {
+class TabsRemoveFunction : public ExtensionFunction {
   ~TabsRemoveFunction() override {}
   ResponseAction Run() override;
   bool RemoveTab(int tab_id, std::string* error);
   DECLARE_EXTENSION_FUNCTION("tabs.remove", TABS_REMOVE)
 };
 class TabsDetectLanguageFunction
-    : public UIThreadExtensionFunction,
+    : public ExtensionFunction,
       public content::WebContentsObserver,
       public translate::ContentTranslateDriver::Observer {
  private:
@@ -209,7 +209,7 @@
 
 class TabsCaptureVisibleTabFunction
     : public extensions::WebContentsCaptureClient,
-      public UIThreadExtensionFunction {
+      public ExtensionFunction {
  public:
   TabsCaptureVisibleTabFunction();
   static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
@@ -280,7 +280,7 @@
   DECLARE_EXTENSION_FUNCTION("tabs.insertCSS", TABS_INSERTCSS)
 };
 
-class TabsSetZoomFunction : public UIThreadExtensionFunction {
+class TabsSetZoomFunction : public ExtensionFunction {
  private:
   ~TabsSetZoomFunction() override {}
 
@@ -289,7 +289,7 @@
   DECLARE_EXTENSION_FUNCTION("tabs.setZoom", TABS_SETZOOM)
 };
 
-class TabsGetZoomFunction : public UIThreadExtensionFunction {
+class TabsGetZoomFunction : public ExtensionFunction {
  private:
   ~TabsGetZoomFunction() override {}
 
@@ -298,7 +298,7 @@
   DECLARE_EXTENSION_FUNCTION("tabs.getZoom", TABS_GETZOOM)
 };
 
-class TabsSetZoomSettingsFunction : public UIThreadExtensionFunction {
+class TabsSetZoomSettingsFunction : public ExtensionFunction {
  private:
   ~TabsSetZoomSettingsFunction() override {}
 
@@ -307,7 +307,7 @@
   DECLARE_EXTENSION_FUNCTION("tabs.setZoomSettings", TABS_SETZOOMSETTINGS)
 };
 
-class TabsGetZoomSettingsFunction : public UIThreadExtensionFunction {
+class TabsGetZoomSettingsFunction : public ExtensionFunction {
  private:
   ~TabsGetZoomSettingsFunction() override {}
 
@@ -316,7 +316,7 @@
   DECLARE_EXTENSION_FUNCTION("tabs.getZoomSettings", TABS_GETZOOMSETTINGS)
 };
 
-class TabsDiscardFunction : public UIThreadExtensionFunction {
+class TabsDiscardFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("tabs.discard", TABS_DISCARD)
 
@@ -331,7 +331,7 @@
   DISALLOW_COPY_AND_ASSIGN(TabsDiscardFunction);
 };
 
-class TabsGoForwardFunction : public UIThreadExtensionFunction {
+class TabsGoForwardFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("tabs.goForward", TABS_GOFORWARD)
 
@@ -346,7 +346,7 @@
   DISALLOW_COPY_AND_ASSIGN(TabsGoForwardFunction);
 };
 
-class TabsGoBackFunction : public UIThreadExtensionFunction {
+class TabsGoBackFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("tabs.goBack", TABS_GOBACK)
 
diff --git a/chrome/browser/extensions/api/tabs/tabs_test.cc b/chrome/browser/extensions/api/tabs/tabs_test.cc
index b6f0fe9f28..f5fb1424 100644
--- a/chrome/browser/extensions/api/tabs/tabs_test.cc
+++ b/chrome/browser/extensions/api/tabs/tabs_test.cc
@@ -795,7 +795,7 @@
 
   int GetTabId(const base::DictionaryValue* value) const;
 
-  base::Value* RunFunction(UIThreadExtensionFunction* function,
+  base::Value* RunFunction(ExtensionFunction* function,
                            const std::string& params);
 
   const Extension* extension() { return extension_.get(); }
@@ -880,7 +880,7 @@
 }
 
 base::Value* ExtensionWindowLastFocusedTest::RunFunction(
-    UIThreadExtensionFunction* function,
+    ExtensionFunction* function,
     const std::string& params) {
   function->set_extension(extension_.get());
   return utils::RunFunctionAndReturnSingleResult(function, params, browser());
diff --git a/chrome/browser/extensions/api/tabs/windows_util.cc b/chrome/browser/extensions/api/tabs/windows_util.cc
index 684183d..ae70d40 100644
--- a/chrome/browser/extensions/api/tabs/windows_util.cc
+++ b/chrome/browser/extensions/api/tabs/windows_util.cc
@@ -23,7 +23,7 @@
 
 namespace windows_util {
 
-bool GetBrowserFromWindowID(UIThreadExtensionFunction* function,
+bool GetBrowserFromWindowID(ExtensionFunction* function,
                             int window_id,
                             extensions::WindowController::TypeFilter filter,
                             Browser** browser,
@@ -68,7 +68,7 @@
   return true;
 }
 
-bool CanOperateOnWindow(const UIThreadExtensionFunction* function,
+bool CanOperateOnWindow(const ExtensionFunction* function,
                         const extensions::WindowController* controller,
                         extensions::WindowController::TypeFilter filter) {
   if (filter && !controller->MatchesFilter(filter))
diff --git a/chrome/browser/extensions/api/tabs/windows_util.h b/chrome/browser/extensions/api/tabs/windows_util.h
index f080d06..551e1bbbb 100644
--- a/chrome/browser/extensions/api/tabs/windows_util.h
+++ b/chrome/browser/extensions/api/tabs/windows_util.h
@@ -9,7 +9,7 @@
 
 #include "chrome/browser/extensions/window_controller_list.h"
 
-class UIThreadExtensionFunction;
+class ExtensionFunction;
 
 namespace extensions {
 class WindowController;
@@ -19,7 +19,7 @@
 
 // Populates |browser| for given |window_id|. If the window is not found,
 // returns false and sets |error|.
-bool GetBrowserFromWindowID(UIThreadExtensionFunction* function,
+bool GetBrowserFromWindowID(ExtensionFunction* function,
                             int window_id,
                             extensions::WindowController::TypeFilter filter,
                             Browser** browser,
@@ -31,7 +31,7 @@
 // kind of window (including app and devtools), otherwise it will
 // return true only for normal browser windows as well as windows
 // created by the extension.
-bool CanOperateOnWindow(const UIThreadExtensionFunction* function,
+bool CanOperateOnWindow(const ExtensionFunction* function,
                         const extensions::WindowController* controller,
                         extensions::WindowController::TypeFilter filter);
 
diff --git a/chrome/browser/extensions/api/terminal/terminal_private_api.h b/chrome/browser/extensions/api/terminal/terminal_private_api.h
index 601c34e..caf14dc1 100644
--- a/chrome/browser/extensions/api/terminal/terminal_private_api.h
+++ b/chrome/browser/extensions/api/terminal/terminal_private_api.h
@@ -13,8 +13,7 @@
 namespace extensions {
 
 // Opens new terminal process. Returns the new terminal id.
-class TerminalPrivateOpenTerminalProcessFunction
-    : public UIThreadExtensionFunction {
+class TerminalPrivateOpenTerminalProcessFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("terminalPrivate.openTerminalProcess",
                              TERMINALPRIVATE_OPENTERMINALPROCESS)
@@ -43,7 +42,7 @@
 
 // Send input to the terminal process specified by the terminal ID, which is set
 // as an argument.
-class TerminalPrivateSendInputFunction : public UIThreadExtensionFunction {
+class TerminalPrivateSendInputFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("terminalPrivate.sendInput",
                              TERMINALPRIVATE_SENDINPUT)
@@ -60,8 +59,7 @@
 };
 
 // Closes terminal process.
-class TerminalPrivateCloseTerminalProcessFunction
-    : public UIThreadExtensionFunction {
+class TerminalPrivateCloseTerminalProcessFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("terminalPrivate.closeTerminalProcess",
                              TERMINALPRIVATE_CLOSETERMINALPROCESS)
@@ -77,8 +75,7 @@
 };
 
 // Called by extension when terminal size changes.
-class TerminalPrivateOnTerminalResizeFunction
-    : public UIThreadExtensionFunction {
+class TerminalPrivateOnTerminalResizeFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("terminalPrivate.onTerminalResize",
                              TERMINALPRIVATE_ONTERMINALRESIZE)
@@ -95,7 +92,7 @@
   void RespondOnUIThread(bool success);
 };
 
-class TerminalPrivateAckOutputFunction : public UIThreadExtensionFunction {
+class TerminalPrivateAckOutputFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("terminalPrivate.ackOutput",
                              TERMINALPRIVATE_ACKOUTPUT)
diff --git a/chrome/browser/extensions/api/top_sites/top_sites_api.h b/chrome/browser/extensions/api/top_sites/top_sites_api.h
index 1b86893..0bcfa27 100644
--- a/chrome/browser/extensions/api/top_sites/top_sites_api.h
+++ b/chrome/browser/extensions/api/top_sites/top_sites_api.h
@@ -10,7 +10,7 @@
 
 namespace extensions {
 
-class TopSitesGetFunction : public UIThreadExtensionFunction {
+class TopSitesGetFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("topSites.get", TOPSITES_GET)
 
diff --git a/chrome/browser/extensions/api/web_navigation/web_navigation_api.h b/chrome/browser/extensions/api/web_navigation/web_navigation_api.h
index d76a63e..99186382 100644
--- a/chrome/browser/extensions/api/web_navigation/web_navigation_api.h
+++ b/chrome/browser/extensions/api/web_navigation/web_navigation_api.h
@@ -179,14 +179,14 @@
 };
 
 // API function that returns the state of a given frame.
-class WebNavigationGetFrameFunction : public UIThreadExtensionFunction {
+class WebNavigationGetFrameFunction : public ExtensionFunction {
   ~WebNavigationGetFrameFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("webNavigation.getFrame", WEBNAVIGATION_GETFRAME)
 };
 
 // API function that returns the states of all frames in a given tab.
-class WebNavigationGetAllFramesFunction : public UIThreadExtensionFunction {
+class WebNavigationGetAllFramesFunction : public ExtensionFunction {
   ~WebNavigationGetAllFramesFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("webNavigation.getAllFrames",
diff --git a/chrome/browser/extensions/api/web_view/chrome_web_view_internal_api.h b/chrome/browser/extensions/api/web_view/chrome_web_view_internal_api.h
index 9ca71ed..b9f6354 100644
--- a/chrome/browser/extensions/api/web_view/chrome_web_view_internal_api.h
+++ b/chrome/browser/extensions/api/web_view/chrome_web_view_internal_api.h
@@ -17,7 +17,7 @@
 namespace extensions {
 
 class ChromeWebViewInternalContextMenusCreateFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("chromeWebViewInternal.contextMenusCreate",
                              WEBVIEWINTERNAL_CONTEXTMENUSCREATE)
@@ -26,7 +26,7 @@
  protected:
   ~ChromeWebViewInternalContextMenusCreateFunction() override {}
 
-  // UIThreadExtensionFunction implementation.
+  // ExtensionFunction implementation.
   ResponseAction Run() override;
 
  private:
@@ -34,7 +34,7 @@
 };
 
 class ChromeWebViewInternalContextMenusUpdateFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("chromeWebViewInternal.contextMenusUpdate",
                              WEBVIEWINTERNAL_CONTEXTMENUSUPDATE)
@@ -43,7 +43,7 @@
  protected:
   ~ChromeWebViewInternalContextMenusUpdateFunction() override {}
 
-  // UIThreadExtensionFunction implementation.
+  // ExtensionFunction implementation.
   ResponseAction Run() override;
 
  private:
@@ -51,7 +51,7 @@
 };
 
 class ChromeWebViewInternalContextMenusRemoveFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("chromeWebViewInternal.contextMenusRemove",
                              WEBVIEWINTERNAL_CONTEXTMENUSREMOVE)
@@ -60,7 +60,7 @@
  protected:
   ~ChromeWebViewInternalContextMenusRemoveFunction() override {}
 
-  // UIThreadExtensionFunction implementation.
+  // ExtensionFunction implementation.
   ResponseAction Run() override;
 
  private:
@@ -68,7 +68,7 @@
 };
 
 class ChromeWebViewInternalContextMenusRemoveAllFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("chromeWebViewInternal.contextMenusRemoveAll",
                              WEBVIEWINTERNAL_CONTEXTMENUSREMOVEALL)
@@ -77,7 +77,7 @@
  protected:
   ~ChromeWebViewInternalContextMenusRemoveAllFunction() override {}
 
-  // UIThreadExtensionFunction implementation.
+  // ExtensionFunction implementation.
   ResponseAction Run() override;
 
  private:
diff --git a/chrome/browser/extensions/api/webrtc_logging_private/webrtc_logging_private_api.cc b/chrome/browser/extensions/api/webrtc_logging_private/webrtc_logging_private_api.cc
index c79032d..8a6d956d 100644
--- a/chrome/browser/extensions/api/webrtc_logging_private/webrtc_logging_private_api.cc
+++ b/chrome/browser/extensions/api/webrtc_logging_private/webrtc_logging_private_api.cc
@@ -287,7 +287,7 @@
 
   // Post a task since this is an asynchronous extension function.
   // TODO(devlin): This is unneccessary; this should just be a
-  // UIThreadExtensionFunction. Fix this.
+  // ExtensionFunction. Fix this.
   base::PostTaskWithTraits(
       FROM_HERE, {BrowserThread::UI},
       base::BindOnce(
diff --git a/chrome/browser/extensions/api/webstore_private/webstore_private_api.h b/chrome/browser/extensions/api/webstore_private/webstore_private_api.h
index 0e74942..72f6544 100644
--- a/chrome/browser/extensions/api/webstore_private/webstore_private_api.h
+++ b/chrome/browser/extensions/api/webstore_private/webstore_private_api.h
@@ -42,7 +42,7 @@
 };
 
 class WebstorePrivateBeginInstallWithManifest3Function
-    : public UIThreadExtensionFunction,
+    : public ExtensionFunction,
       public WebstoreInstallHelper::Delegate {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.beginInstallWithManifest3",
@@ -97,7 +97,7 @@
 };
 
 class WebstorePrivateCompleteInstallFunction
-    : public UIThreadExtensionFunction,
+    : public ExtensionFunction,
       public WebstoreInstaller::Delegate {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.completeInstall",
@@ -126,8 +126,7 @@
   std::unique_ptr<ScopedActiveInstall> scoped_active_install_;
 };
 
-class WebstorePrivateEnableAppLauncherFunction
-    : public UIThreadExtensionFunction {
+class WebstorePrivateEnableAppLauncherFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.enableAppLauncher",
                              WEBSTOREPRIVATE_ENABLEAPPLAUNCHER)
@@ -143,8 +142,7 @@
   ChromeExtensionFunctionDetails chrome_details_;
 };
 
-class WebstorePrivateGetBrowserLoginFunction
-    : public UIThreadExtensionFunction {
+class WebstorePrivateGetBrowserLoginFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.getBrowserLogin",
                              WEBSTOREPRIVATE_GETBROWSERLOGIN)
@@ -160,8 +158,7 @@
   ChromeExtensionFunctionDetails chrome_details_;
 };
 
-class WebstorePrivateGetStoreLoginFunction
-    : public UIThreadExtensionFunction {
+class WebstorePrivateGetStoreLoginFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.getStoreLogin",
                              WEBSTOREPRIVATE_GETSTORELOGIN)
@@ -177,8 +174,7 @@
   ChromeExtensionFunctionDetails chrome_details_;
 };
 
-class WebstorePrivateSetStoreLoginFunction
-    : public UIThreadExtensionFunction {
+class WebstorePrivateSetStoreLoginFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.setStoreLogin",
                              WEBSTOREPRIVATE_SETSTORELOGIN)
@@ -194,8 +190,7 @@
   ChromeExtensionFunctionDetails chrome_details_;
 };
 
-class WebstorePrivateGetWebGLStatusFunction
-    : public UIThreadExtensionFunction {
+class WebstorePrivateGetWebGLStatusFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.getWebGLStatus",
                              WEBSTOREPRIVATE_GETWEBGLSTATUS)
@@ -213,8 +208,7 @@
   scoped_refptr<content::GpuFeatureChecker> feature_checker_;
 };
 
-class WebstorePrivateGetIsLauncherEnabledFunction
-    : public UIThreadExtensionFunction {
+class WebstorePrivateGetIsLauncherEnabledFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.getIsLauncherEnabled",
                              WEBSTOREPRIVATE_GETISLAUNCHERENABLED)
@@ -230,8 +224,7 @@
   void OnIsLauncherCheckCompleted(bool is_enabled);
 };
 
-class WebstorePrivateIsInIncognitoModeFunction
-    : public UIThreadExtensionFunction {
+class WebstorePrivateIsInIncognitoModeFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.isInIncognitoMode",
                              WEBSTOREPRIVATE_ISININCOGNITOMODEFUNCTION)
@@ -247,8 +240,7 @@
   ChromeExtensionFunctionDetails chrome_details_;
 };
 
-class WebstorePrivateLaunchEphemeralAppFunction
-    : public UIThreadExtensionFunction {
+class WebstorePrivateLaunchEphemeralAppFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.launchEphemeralApp",
                              WEBSTOREPRIVATE_LAUNCHEPHEMERALAPP)
@@ -272,7 +264,7 @@
 };
 
 class WebstorePrivateGetEphemeralAppsEnabledFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.getEphemeralAppsEnabled",
                              WEBSTOREPRIVATE_GETEPHEMERALAPPSENABLED)
@@ -287,7 +279,7 @@
 };
 
 class WebstorePrivateIsPendingCustodianApprovalFunction
-    : public UIThreadExtensionFunction {
+    : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.isPendingCustodianApproval",
                              WEBSTOREPRIVATE_ISPENDINGCUSTODIANAPPROVAL)
@@ -305,8 +297,7 @@
   ChromeExtensionFunctionDetails chrome_details_;
 };
 
-class WebstorePrivateGetReferrerChainFunction
-    : public UIThreadExtensionFunction {
+class WebstorePrivateGetReferrerChainFunction : public ExtensionFunction {
  public:
   DECLARE_EXTENSION_FUNCTION("webstorePrivate.getReferrerChain",
                              WEBSTOREPRIVATE_GETREFERRERCHAIN)
diff --git a/chrome/browser/extensions/chrome_extension_function.cc b/chrome/browser/extensions/chrome_extension_function.cc
index 587f441..db287d0 100644
--- a/chrome/browser/extensions/chrome_extension_function.cc
+++ b/chrome/browser/extensions/chrome_extension_function.cc
@@ -30,7 +30,7 @@
 }
 
 const std::string& ChromeAsyncExtensionFunction::GetError() const {
-  return error_.empty() ? UIThreadExtensionFunction::GetError() : error_;
+  return error_.empty() ? ExtensionFunction::GetError() : error_;
 }
 
 void ChromeAsyncExtensionFunction::SendResponse(bool success) {
diff --git a/chrome/browser/extensions/chrome_extension_function.h b/chrome/browser/extensions/chrome_extension_function.h
index a21d33e..dba9bb2 100644
--- a/chrome/browser/extensions/chrome_extension_function.h
+++ b/chrome/browser/extensions/chrome_extension_function.h
@@ -14,10 +14,10 @@
 // A chrome specific analog to AsyncExtensionFunction. This has access to a
 // chrome Profile.
 //
-// DEPRECATED: Inherit directly from UIThreadExtensionFunction.
+// DEPRECATED: Inherit directly from ExtensionFunction.
 // Then if you need access to Chrome details, you can construct a
 // ChromeExtensionFunctionDetails object within your function implementation.
-class ChromeAsyncExtensionFunction : public UIThreadExtensionFunction {
+class ChromeAsyncExtensionFunction : public ExtensionFunction {
  public:
   ChromeAsyncExtensionFunction();
 
@@ -56,7 +56,7 @@
 
  private:
   // If you're hitting a compile error here due to "final" - great! You're doing
-  // the right thing, you just need to extend UIThreadExtensionFunction instead
+  // the right thing, you just need to extend ExtensionFunction instead
   // of ChromeAsyncExtensionFunction.
   ResponseAction Run() final;
 
diff --git a/chrome/browser/extensions/chrome_extension_function_details.cc b/chrome/browser/extensions/chrome_extension_function_details.cc
index d925583..4adaa2ec 100644
--- a/chrome/browser/extensions/chrome_extension_function_details.cc
+++ b/chrome/browser/extensions/chrome_extension_function_details.cc
@@ -21,9 +21,8 @@
 #include "extensions/browser/extension_function_dispatcher.h"
 
 ChromeExtensionFunctionDetails::ChromeExtensionFunctionDetails(
-    UIThreadExtensionFunction* function)
-    : function_(function) {
-}
+    ExtensionFunction* function)
+    : function_(function) {}
 
 ChromeExtensionFunctionDetails::~ChromeExtensionFunctionDetails() {
 }
diff --git a/chrome/browser/extensions/chrome_extension_function_details.h b/chrome/browser/extensions/chrome_extension_function_details.h
index be55786..79f6863 100644
--- a/chrome/browser/extensions/chrome_extension_function_details.h
+++ b/chrome/browser/extensions/chrome_extension_function_details.h
@@ -10,16 +10,16 @@
 
 class Browser;
 class Profile;
-class UIThreadExtensionFunction;
+class ExtensionFunction;
 
-// Provides Chrome-specific details to UIThreadExtensionFunction
+// Provides Chrome-specific details to ExtensionFunction
 // implementations.
 class ChromeExtensionFunctionDetails {
  public:
   // Constructs a new ChromeExtensionFunctionDetails instance for |function|.
   // This instance does not own |function|. |function| must outlive this
   // instance.
-  explicit ChromeExtensionFunctionDetails(UIThreadExtensionFunction* function);
+  explicit ChromeExtensionFunctionDetails(ExtensionFunction* function);
   ~ChromeExtensionFunctionDetails();
 
   Profile* GetProfile() const;
@@ -55,14 +55,14 @@
   // - A browser with the same profile
   gfx::NativeWindow GetNativeWindowForUI();
 
-  // Returns a pointer to the associated UIThreadExtensionFunction
-  UIThreadExtensionFunction* function() { return function_; }
-  const UIThreadExtensionFunction* function() const { return function_; }
+  // Returns a pointer to the associated ExtensionFunction
+  ExtensionFunction* function() { return function_; }
+  const ExtensionFunction* function() const { return function_; }
 
  private:
   // The function for which these details have been created. Must outlive the
   // ChromeExtensionFunctionDetails instance.
-  UIThreadExtensionFunction* function_;
+  ExtensionFunction* function_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeExtensionFunctionDetails);
 };
diff --git a/chrome/browser/extensions/chrome_extension_function_unittest.cc b/chrome/browser/extensions/chrome_extension_function_unittest.cc
index 9d3fe1a..d5305a41 100644
--- a/chrome/browser/extensions/chrome_extension_function_unittest.cc
+++ b/chrome/browser/extensions/chrome_extension_function_unittest.cc
@@ -31,7 +31,7 @@
   *did_respond = true;
 }
 
-class ValidationFunction : public UIThreadExtensionFunction {
+class ValidationFunction : public ExtensionFunction {
  public:
   explicit ValidationFunction(bool should_succeed)
       : should_succeed_(should_succeed), did_respond_(false) {
diff --git a/chrome/browser/extensions/extension_api_unittest.cc b/chrome/browser/extensions/extension_api_unittest.cc
index b28dfcad..ebc9dd9 100644
--- a/chrome/browser/extensions/extension_api_unittest.cc
+++ b/chrome/browser/extensions/extension_api_unittest.cc
@@ -29,7 +29,7 @@
 }
 
 std::unique_ptr<base::Value> ExtensionApiUnittest::RunFunctionAndReturnValue(
-    UIThreadExtensionFunction* function,
+    ExtensionFunction* function,
     const std::string& args) {
   function->set_extension(extension());
   return std::unique_ptr<base::Value>(
@@ -38,7 +38,7 @@
 
 std::unique_ptr<base::DictionaryValue>
 ExtensionApiUnittest::RunFunctionAndReturnDictionary(
-    UIThreadExtensionFunction* function,
+    ExtensionFunction* function,
     const std::string& args) {
   base::Value* value = RunFunctionAndReturnValue(function, args).release();
   base::DictionaryValue* dict = NULL;
@@ -53,7 +53,7 @@
 }
 
 std::unique_ptr<base::ListValue> ExtensionApiUnittest::RunFunctionAndReturnList(
-    UIThreadExtensionFunction* function,
+    ExtensionFunction* function,
     const std::string& args) {
   base::Value* value = RunFunctionAndReturnValue(function, args).release();
   base::ListValue* list = NULL;
@@ -68,13 +68,14 @@
 }
 
 std::string ExtensionApiUnittest::RunFunctionAndReturnError(
-    UIThreadExtensionFunction* function, const std::string& args) {
+    ExtensionFunction* function,
+    const std::string& args) {
   function->set_extension(extension());
   return utils::RunFunctionAndReturnError(function, args, browser());
 }
 
-void ExtensionApiUnittest::RunFunction(
-    UIThreadExtensionFunction* function, const std::string& args) {
+void ExtensionApiUnittest::RunFunction(ExtensionFunction* function,
+                                       const std::string& args) {
   RunFunctionAndReturnValue(function, args);
 }
 
diff --git a/chrome/browser/extensions/extension_api_unittest.h b/chrome/browser/extensions/extension_api_unittest.h
index b4922eb..8ddb90b 100644
--- a/chrome/browser/extensions/extension_api_unittest.h
+++ b/chrome/browser/extensions/extension_api_unittest.h
@@ -17,7 +17,7 @@
 class ListValue;
 }
 
-class UIThreadExtensionFunction;
+class ExtensionFunction;
 
 namespace extensions {
 
@@ -54,29 +54,28 @@
 
   // Return the function result as a base::Value.
   std::unique_ptr<base::Value> RunFunctionAndReturnValue(
-      UIThreadExtensionFunction* function,
+      ExtensionFunction* function,
       const std::string& args);
 
   // Return the function result as a base::DictionaryValue, or NULL.
   // This will EXPECT-fail if the result is not a DictionaryValue.
   std::unique_ptr<base::DictionaryValue> RunFunctionAndReturnDictionary(
-      UIThreadExtensionFunction* function,
+      ExtensionFunction* function,
       const std::string& args);
 
   // Return the function result as a base::ListValue, or NULL.
   // This will EXPECT-fail if the result is not a ListValue.
   std::unique_ptr<base::ListValue> RunFunctionAndReturnList(
-      UIThreadExtensionFunction* function,
+      ExtensionFunction* function,
       const std::string& args);
 
   // Return an error thrown from the function, if one exists.
   // This will EXPECT-fail if any result is returned from the function.
-  std::string RunFunctionAndReturnError(
-      UIThreadExtensionFunction* function, const std::string& args);
+  std::string RunFunctionAndReturnError(ExtensionFunction* function,
+                                        const std::string& args);
 
   // Run the function and ignore any result.
-  void RunFunction(
-      UIThreadExtensionFunction* function, const std::string& args);
+  void RunFunction(ExtensionFunction* function, const std::string& args);
 
  private:
   // The Extension used when running API function calls.
diff --git a/chrome/browser/extensions/extension_function_test_utils.cc b/chrome/browser/extensions/extension_function_test_utils.cc
index edf3ff8..f6a0e27 100644
--- a/chrome/browser/extensions/extension_function_test_utils.cc
+++ b/chrome/browser/extensions/extension_function_test_utils.cc
@@ -83,14 +83,14 @@
   return false;
 }
 
-std::string RunFunctionAndReturnError(UIThreadExtensionFunction* function,
+std::string RunFunctionAndReturnError(ExtensionFunction* function,
                                       const std::string& args,
                                       Browser* browser) {
   return RunFunctionAndReturnError(function, args, browser,
                                    extensions::api_test_utils::NONE);
 }
 std::string RunFunctionAndReturnError(
-    UIThreadExtensionFunction* function,
+    ExtensionFunction* function,
     const std::string& args,
     Browser* browser,
     extensions::api_test_utils::RunFunctionFlags flags) {
@@ -106,15 +106,14 @@
   return function->GetError();
 }
 
-base::Value* RunFunctionAndReturnSingleResult(
-    UIThreadExtensionFunction* function,
-    const std::string& args,
-    Browser* browser) {
+base::Value* RunFunctionAndReturnSingleResult(ExtensionFunction* function,
+                                              const std::string& args,
+                                              Browser* browser) {
   return RunFunctionAndReturnSingleResult(function, args, browser,
                                           extensions::api_test_utils::NONE);
 }
 base::Value* RunFunctionAndReturnSingleResult(
-    UIThreadExtensionFunction* function,
+    ExtensionFunction* function,
     const std::string& args,
     Browser* browser,
     extensions::api_test_utils::RunFunctionFlags flags) {
@@ -130,7 +129,7 @@
   return NULL;
 }
 
-bool RunFunction(UIThreadExtensionFunction* function,
+bool RunFunction(ExtensionFunction* function,
                  const std::string& args,
                  Browser* browser,
                  extensions::api_test_utils::RunFunctionFlags flags) {
@@ -140,7 +139,7 @@
   return RunFunction(function, std::move(parsed_args), browser, flags);
 }
 
-bool RunFunction(UIThreadExtensionFunction* function,
+bool RunFunction(ExtensionFunction* function,
                  std::unique_ptr<base::ListValue> args,
                  Browser* browser,
                  extensions::api_test_utils::RunFunctionFlags flags) {
diff --git a/chrome/browser/extensions/extension_function_test_utils.h b/chrome/browser/extensions/extension_function_test_utils.h
index 27976b63..b6b70f7b 100644
--- a/chrome/browser/extensions/extension_function_test_utils.h
+++ b/chrome/browser/extensions/extension_function_test_utils.h
@@ -12,7 +12,7 @@
 #include "extensions/common/manifest.h"
 
 class Browser;
-class UIThreadExtensionFunction;
+class ExtensionFunction;
 
 namespace base {
 class Value;
@@ -43,11 +43,11 @@
 // the current test if |function| returns a result. Takes ownership of
 // |function|.
 std::string RunFunctionAndReturnError(
-    UIThreadExtensionFunction* function,
+    ExtensionFunction* function,
     const std::string& args,
     Browser* browser,
     extensions::api_test_utils::RunFunctionFlags flags);
-std::string RunFunctionAndReturnError(UIThreadExtensionFunction* function,
+std::string RunFunctionAndReturnError(ExtensionFunction* function,
                                       const std::string& args,
                                       Browser* browser);
 
@@ -55,14 +55,13 @@
 // current test if |function| returns an error. Takes ownership of
 // |function|. The caller takes ownership of the result.
 base::Value* RunFunctionAndReturnSingleResult(
-    UIThreadExtensionFunction* function,
+    ExtensionFunction* function,
     const std::string& args,
     Browser* browser,
     extensions::api_test_utils::RunFunctionFlags flags);
-base::Value* RunFunctionAndReturnSingleResult(
-    UIThreadExtensionFunction* function,
-    const std::string& args,
-    Browser* browser);
+base::Value* RunFunctionAndReturnSingleResult(ExtensionFunction* function,
+                                              const std::string& args,
+                                              Browser* browser);
 
 // Create and run |function| with |args|. Works with both synchronous and async
 // functions. Ownership of |function| remains with the caller.
@@ -74,11 +73,11 @@
 // TODO(aa): I'm concerned that this style won't scale to all the bits and bobs
 // we're going to need to frob for all the different extension functions. But
 // we can refactor when we see what is needed.
-bool RunFunction(UIThreadExtensionFunction* function,
+bool RunFunction(ExtensionFunction* function,
                  const std::string& args,
                  Browser* browser,
                  extensions::api_test_utils::RunFunctionFlags flags);
-bool RunFunction(UIThreadExtensionFunction* function,
+bool RunFunction(ExtensionFunction* function,
                  std::unique_ptr<base::ListValue> args,
                  Browser* browser,
                  extensions::api_test_utils::RunFunctionFlags flags);
diff --git a/chrome/browser/extensions/extension_tab_util.cc b/chrome/browser/extensions/extension_tab_util.cc
index d508ef4..18b81d0 100644
--- a/chrome/browser/extensions/extension_tab_util.cc
+++ b/chrome/browser/extensions/extension_tab_util.cc
@@ -129,11 +129,10 @@
 
 // Opens a new tab for a given extension. Returns nullptr and sets |error| if an
 // error occurs.
-base::DictionaryValue* ExtensionTabUtil::OpenTab(
-    UIThreadExtensionFunction* function,
-    const OpenTabParams& params,
-    bool user_gesture,
-    std::string* error) {
+base::DictionaryValue* ExtensionTabUtil::OpenTab(ExtensionFunction* function,
+                                                 const OpenTabParams& params,
+                                                 bool user_gesture,
+                                                 std::string* error) {
   ChromeExtensionFunctionDetails chrome_details(function);
   Profile* profile = chrome_details.GetProfile();
   // windowId defaults to "current" window.
diff --git a/chrome/browser/extensions/extension_tab_util.h b/chrome/browser/extensions/extension_tab_util.h
index f255bc7c..c873ae0176 100644
--- a/chrome/browser/extensions/extension_tab_util.h
+++ b/chrome/browser/extensions/extension_tab_util.h
@@ -16,7 +16,7 @@
 class ChromeExtensionFunctionDetails;
 class GURL;
 class TabStripModel;
-class UIThreadExtensionFunction;
+class ExtensionFunction;
 
 namespace base {
 class DictionaryValue;
@@ -75,7 +75,7 @@
   // Opens a new tab given an extension function |function| and creation
   // parameters |params|. Returns a Tab object if successful, or NULL and
   // optionally sets |error| if an error occurs.
-  static base::DictionaryValue* OpenTab(UIThreadExtensionFunction* function,
+  static base::DictionaryValue* OpenTab(ExtensionFunction* function,
                                         const OpenTabParams& params,
                                         bool user_gesture,
                                         std::string* error);
diff --git a/chrome/browser/extensions/window_controller_list.cc b/chrome/browser/extensions/window_controller_list.cc
index d419073..74042cc 100644
--- a/chrome/browser/extensions/window_controller_list.cc
+++ b/chrome/browser/extensions/window_controller_list.cc
@@ -55,7 +55,7 @@
 }
 
 WindowController* WindowControllerList::FindWindowForFunctionByIdWithFilter(
-    const UIThreadExtensionFunction* function,
+    const ExtensionFunction* function,
     int id,
     WindowController::TypeFilter filter) const {
   for (auto iter = windows().begin(); iter != windows().end(); ++iter) {
@@ -69,13 +69,13 @@
 }
 
 WindowController* WindowControllerList::CurrentWindowForFunction(
-    const UIThreadExtensionFunction* function) const {
+    const ExtensionFunction* function) const {
   return CurrentWindowForFunctionWithFilter(function,
                                             WindowController::kNoWindowFilter);
 }
 
 WindowController* WindowControllerList::CurrentWindowForFunctionWithFilter(
-    const UIThreadExtensionFunction* function,
+    const ExtensionFunction* function,
     WindowController::TypeFilter filter) const {
   WindowController* result = nullptr;
   // Returns either the focused window (if any), or the last window in the list.
diff --git a/chrome/browser/extensions/window_controller_list.h b/chrome/browser/extensions/window_controller_list.h
index 5081543f..47f978c 100644
--- a/chrome/browser/extensions/window_controller_list.h
+++ b/chrome/browser/extensions/window_controller_list.h
@@ -13,7 +13,7 @@
 #include "base/observer_list.h"
 #include "chrome/browser/extensions/window_controller.h"
 
-class UIThreadExtensionFunction;
+class ExtensionFunction;
 
 namespace extensions {
 
@@ -36,19 +36,19 @@
   // Returns a window matching the context the function was invoked in
   // using |filter|.
   WindowController* FindWindowForFunctionByIdWithFilter(
-      const UIThreadExtensionFunction* function,
+      const ExtensionFunction* function,
       int id,
       WindowController::TypeFilter filter) const;
 
   // Returns the focused or last added window matching the context the function
   // was invoked in.
   WindowController* CurrentWindowForFunction(
-      const UIThreadExtensionFunction* function) const;
+      const ExtensionFunction* function) const;
 
   // Returns the focused or last added window matching the context the function
   // was invoked in using |filter|.
   WindowController* CurrentWindowForFunctionWithFilter(
-      const UIThreadExtensionFunction* function,
+      const ExtensionFunction* function,
       WindowController::TypeFilter filter) const;
 
   const ControllerList& windows() const { return windows_; }
diff --git a/chrome/browser/speech/extension_api/tts_engine_extension_api.h b/chrome/browser/speech/extension_api/tts_engine_extension_api.h
index 9c358ea..c8c2a73 100644
--- a/chrome/browser/speech/extension_api/tts_engine_extension_api.h
+++ b/chrome/browser/speech/extension_api/tts_engine_extension_api.h
@@ -40,8 +40,7 @@
 
 // Function that allows tts engines to update its list of supported voices at
 // runtime.
-class ExtensionTtsEngineUpdateVoicesFunction
-    : public UIThreadExtensionFunction {
+class ExtensionTtsEngineUpdateVoicesFunction : public ExtensionFunction {
  private:
   ~ExtensionTtsEngineUpdateVoicesFunction() override {}
   ResponseAction Run() override;
@@ -50,8 +49,7 @@
 
 // Hidden/internal extension function used to allow TTS engine extensions
 // to send events back to the client that's calling tts.speak().
-class ExtensionTtsEngineSendTtsEventFunction
-    : public UIThreadExtensionFunction {
+class ExtensionTtsEngineSendTtsEventFunction : public ExtensionFunction {
  private:
   ~ExtensionTtsEngineSendTtsEventFunction() override {}
   ResponseAction Run() override;
diff --git a/chrome/browser/speech/extension_api/tts_extension_api.h b/chrome/browser/speech/extension_api/tts_extension_api.h
index 7caeda6..db88b08 100644
--- a/chrome/browser/speech/extension_api/tts_extension_api.h
+++ b/chrome/browser/speech/extension_api/tts_extension_api.h
@@ -27,35 +27,35 @@
   DECLARE_EXTENSION_FUNCTION("tts.speak", TTS_SPEAK)
 };
 
-class TtsStopSpeakingFunction : public UIThreadExtensionFunction {
+class TtsStopSpeakingFunction : public ExtensionFunction {
  private:
   ~TtsStopSpeakingFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tts.stop", TTS_STOP)
 };
 
-class TtsPauseFunction : public UIThreadExtensionFunction {
+class TtsPauseFunction : public ExtensionFunction {
  private:
   ~TtsPauseFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tts.pause", TTS_PAUSE)
 };
 
-class TtsResumeFunction : public UIThreadExtensionFunction {
+class TtsResumeFunction : public ExtensionFunction {
  private:
   ~TtsResumeFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tts.resume", TTS_RESUME)
 };
 
-class TtsIsSpeakingFunction : public UIThreadExtensionFunction {
+class TtsIsSpeakingFunction : public ExtensionFunction {
  private:
   ~TtsIsSpeakingFunction() override {}
   ResponseAction Run() override;
   DECLARE_EXTENSION_FUNCTION("tts.isSpeaking", TTS_ISSPEAKING)
 };
 
-class TtsGetVoicesFunction : public UIThreadExtensionFunction {
+class TtsGetVoicesFunction : public ExtensionFunction {
  private:
   ~TtsGetVoicesFunction() override {}
   ResponseAction Run() override;