[Sync] Don't display passphrase notification if user dismissed previous one

chrome/browser/sync/sync_error_notifier_ash.h

Index: chrome/browser/sync/sync_error_notifier_ash.h
diff --git a/chrome/browser/sync/sync_error_notifier_ash.h b/chrome/browser/sync/sync_error_notifier_ash.h
index 4dcc8d29b80600b944746da672a4797dec065a7f..4d572fd6892bd003be61a3a0770a50e9d1bfda30 100644
--- a/chrome/browser/sync/sync_error_notifier_ash.h
+++ b/chrome/browser/sync/sync_error_notifier_ash.h
@@ -35,6 +35,11 @@ class SyncErrorNotifier : public syncer::SyncErrorController::Observer,
   // The Profile this service belongs to.
   Profile* profile_;
 
+  // Notification was added to NotificationUIManager. This flag is used to
+  // prevent displaying passphrase notification to user if they already saw (and
+  // potentially dismissed) previous one.
+  bool notification_displayed_;
+
   // Used to keep track of the message center notification.
   std::string notification_id_;