[Android] Add enhanced bookmark opt-in flag.

chrome/browser/bookmarks/enhanced_bookmarks_features.cc

Index: chrome/browser/bookmarks/enhanced_bookmarks_features.cc
diff --git a/chrome/browser/bookmarks/enhanced_bookmarks_features.cc b/chrome/browser/bookmarks/enhanced_bookmarks_features.cc
index 6f4b36b25ef47361c5f24a787bc46c1a46f3b9f2..b1237632f05d229e4bc389538d8a10350607f98e 100644
--- a/chrome/browser/bookmarks/enhanced_bookmarks_features.cc
+++ b/chrome/browser/bookmarks/enhanced_bookmarks_features.cc
@@ -10,8 +10,12 @@
 #include "base/prefs/scoped_user_pref_update.h"
 #include "base/sha1.h"
 #include "base/strings/string_number_conversions.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/signin/signin_manager_factory.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
+#include "components/signin/core/browser/signin_manager.h"
 #include "components/sync_driver/pref_names.h"
 #include "components/variations/variations_associated_data.h"
 #include "extensions/common/features/feature.h"
@@ -129,6 +133,14 @@ void UpdateBookmarksExperimentState(
     }
   }
 
+#if defined(OS_ANDROID)
+  bool opt_in = !opt_out
+      && CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
+          switches::kEnhancedBookmarksExperiment) == "1";
+  if (opt_in && bookmarks_experiment_new_state == BOOKMARKS_EXPERIMENT_NONE)
+    bookmarks_experiment_new_state = BOOKMARKS_EXPERIMENT_ENABLED;
+#endif
+
   UMA_HISTOGRAM_ENUMERATION("EnhancedBookmarks.SyncExperimentState",
                             bookmarks_experiment_new_state,
                             BOOKMARKS_EXPERIMENT_ENUM_SIZE);
@@ -139,6 +151,16 @@ void UpdateBookmarksExperimentState(
                                        bookmarks_experiment_new_state);
 }
 
+void InitBookmarksExperimentState(Profile* profile) {
+  SigninManagerBase* signin = SigninManagerFactory::GetForProfile(profile);
+  bool is_signed_in = signin && !signin->IsAuthenticated();
+  UpdateBookmarksExperimentState(
+      profile->GetPrefs(),
+      g_browser_process->local_state(),
+      is_signed_in,
+      BOOKMARKS_EXPERIMENT_ENABLED_FROM_SYNC_UNKNOWN);
+}
+
 void ForceFinchBookmarkExperimentIfNeeded(
     PrefService* flags_storage,
     BookmarksExperimentState bookmarks_experiment_state) {