LaCrOS: Replace defined(OS_CHROMEOS) with BUILDFLAG(IS_CHROMEOS_ASH)

The change is mostly mechanical replacing defined(OS_CHROMEOS) with
BUILDFLAG(IS_CHROMEOS_ASH) and GN variable is_chromeos with
is_chromeos_ash with some special cases (For those cases please
refer to http://go/lacros-macros).

The patch is made in preparation to switching lacros build from
target_os=linux to target_os=chromeos. This will prevent lacros from
changing behaviour after the switch.

Bug: 1052397
Change-Id: I342e1ca6cef8b69bafae5de2d4b446a1eacd6f3b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2564980
Commit-Queue: Yuta Hijikata <[email protected]>
Reviewed-by: Dirk Pranke <[email protected]>
Reviewed-by: Dominick Ng <[email protected]>
Reviewed-by: Avi Drissman <[email protected]>
Cr-Commit-Position: refs/heads/master@{#834552}
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 20d2e226..205d869 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -9,6 +9,7 @@
 #include "base/check_op.h"
 #include "build/build_config.h"
 #include "build/buildflag.h"
+#include "build/chromeos_buildflags.h"
 #include "chrome/common/buildflags.h"
 #include "components/nacl/common/buildflags.h"
 #include "components/paint_preview/buildflags/buildflags.h"
@@ -2114,7 +2115,7 @@
 
 // Chrome OS ------------------------------------------------------------------
 
-#if defined(OS_CHROMEOS)
+#if BUILDFLAG(IS_CHROMEOS_ASH)
 
 extern const char kAccountManagementFlowsV2Name[];
 extern const char kAccountManagementFlowsV2Description[];
@@ -2735,7 +2736,7 @@
 
 // Prefer keeping this section sorted to adding new declarations down here.
 
-#endif  // #if defined(OS_CHROMEOS)
+#endif  // #if BUILDFLAG(IS_CHROMEOS_ASH)
 
 // All views-based platforms --------------------------------------------------
 
@@ -2790,12 +2791,12 @@
 #endif  // defined(OS_WIN) || defined(OS_MAC) || defined(OS_LINUX) ||
         // defined(OS_CHROMEOS)
 
-#if defined(OS_WIN) || defined(OS_MAC) || defined(OS_CHROMEOS)
+#if defined(OS_WIN) || defined(OS_MAC) || BUILDFLAG(IS_CHROMEOS_ASH)
 
 extern const char kWebContentsOcclusionName[];
 extern const char kWebContentsOcclusionDescription[];
 
-#endif  // defined(OS_WIN) || defined(OS_MAC) || defined(OS_CHROMEOS)
+#endif  // defined(OS_WIN) || defined(OS_MAC) || BUILDFLAG(IS_CHROMEOS_ASH)
 
 #if defined(OS_CHROMEOS) || defined(OS_LINUX)
 #if BUILDFLAG(USE_TCMALLOC)
@@ -2804,17 +2805,19 @@
 #endif  // BUILDFLAG(USE_TCMALLOC)
 #endif  // #if defined(OS_CHROMEOS) || defined(OS_LINUX)
 
-#if !defined(OS_ANDROID) && !defined(OS_CHROMEOS)
+#if !defined(OS_ANDROID) && !BUILDFLAG(IS_CHROMEOS_ASH)
 extern const char kUserDataSnapshotName[];
 extern const char kUserDataSnapshotDescription[];
-#endif  // !defined(OS_ANDROID) && !defined(OS_CHROMEOS)
+#endif  // !defined(OS_ANDROID) && !BUILDFLAG(IS_CHROMEOS_ASH)
 
-#if defined(OS_WIN) || defined(OS_CHROMEOS)
+#if defined(OS_WIN) || BUILDFLAG(IS_CHROMEOS_ASH)
 extern const char kWebShareName[];
 extern const char kWebShareDescription[];
-#endif  // defined(OS_WIN) || defined(OS_CHROMEOS)
+#endif  // defined(OS_WIN) || BUILDFLAG(IS_CHROMEOS_ASH)
 
-#if defined(OS_WIN) || (defined(OS_LINUX) && !defined(OS_CHROMEOS)) || \
+// TODO(crbug.com/1052397): Revisit the macro expression once build flag switch
+// of lacros-chrome is complete.
+#if defined(OS_WIN) || (defined(OS_LINUX) || BUILDFLAG(IS_CHROMEOS_LACROS)) || \
     defined(OS_MAC)
 extern const char kEnableEphemeralGuestProfilesOnDesktopName[];
 extern const char kEnableEphemeralGuestProfilesOnDesktopDescription[];
@@ -2868,10 +2871,10 @@
 extern const char kWebUITabStripDescription[];
 #endif  // BUILDFLAG(ENABLE_WEBUI_TAB_STRIP)
 
-#if BUILDFLAG(ENABLE_WEBUI_TAB_STRIP) && defined(OS_CHROMEOS)
+#if BUILDFLAG(ENABLE_WEBUI_TAB_STRIP) && BUILDFLAG(IS_CHROMEOS_ASH)
 extern const char kWebUITabStripTabDragIntegrationName[];
 extern const char kWebUITabStripTabDragIntegrationDescription[];
-#endif  // BUILDFLAG(ENABLE_WEBUI_TAB_STRIP) && defined(OS_CHROMEOS)
+#endif  // BUILDFLAG(ENABLE_WEBUI_TAB_STRIP) && BUILDFLAG(IS_CHROMEOS_ASH)
 
 #if defined(TOOLKIT_VIEWS) || defined(OS_ANDROID)