Surfacing chrome://flags to enable context menu performance info.

This also changes feature flag behavior so that the PerformanceHintsObserver is enabled when kContextMenuPerformanceInfo is enabled. Enabling the UI without enabling the Observer is not a scenario we're interested in.

Bug: 1040661
Change-Id: I4970534ad4b21127ef603955c2b22bb7f5ce40dd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2067690
Commit-Queue: Josh Simmons <[email protected]>
Reviewed-by: David Trainor <[email protected]>
Cr-Commit-Position: refs/heads/master@{#744360}
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index ca3b6965..2b4691d 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -4948,6 +4948,13 @@
      flag_descriptions::kPasswordChangeDescription, kOsAll,
      FEATURE_VALUE_TYPE(password_manager::features::kPasswordChange)},
 
+#if defined(OS_ANDROID)
+    {"context-menu-performance-info",
+     flag_descriptions::kContextMenuPerformanceInfoName,
+     flag_descriptions::kContextMenuPerformanceInfoDescription, kOsAndroid,
+     FEATURE_VALUE_TYPE(chrome::android::kContextMenuPerformanceInfo)},
+#endif  // !defined(OS_ANDROID)
+
     // NOTE: Adding a new flag requires adding a corresponding entry to enum
     // "LoginCustomFlags" in tools/metrics/histograms/enums.xml. See "Flag
     // Histograms" in tools/metrics/histograms/README.md (run the