Skip enhanced bookmarks cluster requests if it's not being used.

chrome/browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service.h

Index: chrome/browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service.h
diff --git a/chrome/browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service.h b/chrome/browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service.h
index 71820e908360ea78d219445f564b34a5e7715d33..47d18fd3c5e1027842b39ddcc53349eae36b0e77 100644
--- a/chrome/browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service.h
+++ b/chrome/browser/enhanced_bookmarks/chrome_bookmark_server_cluster_service.h
@@ -26,6 +26,9 @@ class ChromeBookmarkServerClusterService : public BookmarkServerClusterService,
       ProfileSyncService* sync_service);
   virtual ~ChromeBookmarkServerClusterService();
 
+  // BookmarkServerClusterService
+  virtual void AddObserver(BookmarkServerServiceObserver* observer);

[Mark, 2014/10/20 18:40:43]

I take it this still needs to be wired up somewhere in order to make this new
functionality work?  Sorry, I don't have the full context on these changes.

[danduong, 2014/10/20 18:45:38]

Do we want an override keyword here?

[Kibeom Kim (inactive), 2014/10/20 20:05:47]

override Done.

Yes we're calling |AddObserver(...)| here
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/browser/and...
only when we launch the bookmark UI. So it's already hooked up.

+
   // ProfileSyncServiceObserver implementation.
   virtual void OnStateChanged() override;
   virtual void OnSyncCycleCompleted() override;
@@ -33,6 +36,7 @@ class ChromeBookmarkServerClusterService : public BookmarkServerClusterService,
  private:
   // This class observes the sync service for changes.
   ProfileSyncService* sync_service_;
+  bool sync_refresh_skipped_ = false;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeBookmarkServerClusterService);
 };