[Android] Use the correct enhanced bookmarks enabling logic.

Previously, Android's enhanced bookmarks feature depended on
--manual-enhanced-bookmarks flag and nothing else. But the
correct way is to use UpdateBookmarksExperimentState function's logic,
which desktop has been using.

BUG=386785

Review URL: https://codereview.chromium.org/497563002

Cr-Commit-Position: refs/heads/master@{#293509}

chrome/android/java/src/org/chromium/chrome/browser/BookmarksBridge.java

@@ -344,6 +344,10 @@ public class BookmarksBridge {
         return nativeIsEditBookmarksEnabled();
     }
 
+    public static boolean isEnhancedBookmarksEnabled(Profile profile) {
+        return nativeIsEnhancedBookmarksFeatureEnabled(profile);
+    }
+
     @CalledByNative
     private void bookmarkModelLoaded() {
         mIsNativeBookmarkModelLoaded = true;
@@ -474,6 +478,7 @@ public class BookmarksBridge {
     private native void nativeMoveBookmark(long nativeBookmarksBridge, BookmarkId bookmarkId,
             BookmarkId newParentId, int index);
     private static native long nativeGetNativeBookmarkModel(Profile profile);
+    private static native boolean nativeIsEnhancedBookmarksFeatureEnabled(Profile profile);
     private native long nativeInit(Profile profile);
     private native void nativeDestroy(long nativeBookmarksBridge);
     private static native boolean nativeIsEditBookmarksEnabled();

chrome/browser/about_flags.cc

@@ -1594,7 +1594,7 @@ const Experiment kExperiments[] = {
     "enhanced-bookmarks-experiment",
     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_NAME,
     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_DESCRIPTION,
-    kOsDesktop,
+    kOsDesktop | kOsAndroid,
     ENABLE_DISABLE_VALUE_TYPE_AND_VALUE(
         switches::kEnhancedBookmarksExperiment, "1",
         switches::kEnhancedBookmarksExperiment, "0")
@@ -1603,14 +1603,14 @@ const Experiment kExperiments[] = {
     "manual-enhanced-bookmarks",
     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_NAME,
     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_DESCRIPTION,
-    kOsDesktop,
+    kOsDesktop | kOsAndroid,
     SINGLE_VALUE_TYPE(switches::kManualEnhancedBookmarks)
   },
   {
     "manual-enhanced-bookmarks-optout",
     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_NAME,
     IDS_FLAGS_ENABLE_ENHANCED_BOOKMARKS_DESCRIPTION,
-    kOsDesktop,
+    kOsDesktop | kOsAndroid,
     SINGLE_VALUE_TYPE(switches::kManualEnhancedBookmarksOptout)
   },
 #if defined(OS_ANDROID)

chrome/browser/android/bookmarks/bookmarks_bridge.cc

@@ -10,6 +10,7 @@
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/bookmarks/bookmark_model_factory.h"
 #include "chrome/browser/bookmarks/chrome_bookmark_client_factory.h"
+#include "chrome/browser/bookmarks/enhanced_bookmarks_features.h"
 #include "chrome/browser/profiles/incognito_helpers.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_android.h"
@@ -124,11 +125,18 @@ static jlong Init(JNIEnv* env, jobject obj, jobject j_profile) {
 static jlong GetNativeBookmarkModel(JNIEnv* env,
                                     jclass caller,
                                     jobject j_profile) {
-  Profile *profile = ProfileAndroid::FromProfileAndroid(j_profile);
+  Profile* profile = ProfileAndroid::FromProfileAndroid(j_profile);
   BookmarkModel *bookmark_model_ = BookmarkModelFactory::GetForProfile(profile);
   return reinterpret_cast<jlong>(bookmark_model_);
 }
 
+static jboolean IsEnhancedBookmarksFeatureEnabled(JNIEnv* env,
+                                                  jclass clazz,
+                                                  jobject j_profile) {
+  Profile* profile = ProfileAndroid::FromProfileAndroid(j_profile);
+  return IsEnhancedBookmarksEnabled(profile->GetPrefs());
+}
+
 static bool IsEditBookmarksEnabled() {
   return ProfileManager::GetLastUsedProfile()->GetPrefs()->GetBoolean(
       bookmarks::prefs::kEditBookmarksEnabled);

chrome/browser/bookmarks/enhanced_bookmarks_features.cc

@@ -179,8 +179,8 @@ bool IsEnhancedBookmarksExperimentEnabled() {
 }
 
 #if defined(OS_ANDROID)
-bool IsEnhancedBookmarkImageFetchingEnabled() {
-  if (IsEnhancedBookmarksExperimentEnabled())
+bool IsEnhancedBookmarkImageFetchingEnabled(const PrefService* user_prefs) {
+  if (IsEnhancedBookmarksEnabled(user_prefs))
     return true;
 
   // Salient images are collected from visited bookmarked pages even if the
@@ -192,6 +192,14 @@ bool IsEnhancedBookmarkImageFetchingEnabled() {
       kFieldTrialName, "DisableImagesFetching");
   return disable_fetching.empty();
 }
+
+bool IsEnhancedBookmarksEnabled(const PrefService* user_prefs) {
+  BookmarksExperimentState bookmarks_experiment_state =
+      static_cast<BookmarksExperimentState>(user_prefs->GetInteger(
+          sync_driver::prefs::kEnhancedBookmarksExperimentEnabled));
+  return bookmarks_experiment_state == BOOKMARKS_EXPERIMENT_ENABLED ||
+      bookmarks_experiment_state == BOOKMARKS_EXPERIMENT_ENABLED_FROM_FINCH;
+}
 #endif
 
 bool IsEnableDomDistillerSet() {

chrome/browser/bookmarks/enhanced_bookmarks_features.h

@@ -43,12 +43,20 @@ void ForceFinchBookmarkExperimentIfNeeded(
     PrefService* local_state,
     BookmarksExperimentState bookmarks_experiment_state);
 
-// Returns true if enhanced bookmarks experiment is enabled.
-// Experiment could be enable from Chrome sync or from Finch.
+// Returns true if enhanced bookmarks experiment is running.
+// Experiment could run by Chrome sync or by Finch.
+// Note that this doesn't necessarily mean that enhanced bookmarks
+// is enabled, e.g., user can opt out using a flag.
 bool IsEnhancedBookmarksExperimentEnabled();
 
 #if defined(OS_ANDROID)
-bool IsEnhancedBookmarkImageFetchingEnabled();
+// Returns true if enhanced bookmark salient image prefetching is enabled.
+// This can be controlled by field trial.
+bool IsEnhancedBookmarkImageFetchingEnabled(const PrefService* user_prefs);
+
+// Returns true if enhanced bookmarks is enabled.
+bool IsEnhancedBookmarksEnabled(const PrefService* user_prefs);
+
 #endif
 
 // Returns true when flag enable-dom-distiller is set or enabled from Finch.