Add shutdown notification and service refs to SyncServiceObserver.

chrome/browser/sync/sync_startup_tracker.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_SYNC_SYNC_STARTUP_TRACKER_H_
 #define CHROME_BROWSER_SYNC_SYNC_STARTUP_TRACKER_H_
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "components/sync/driver/sync_service_observer.h"
@@ skipping 28 matching lines @@
     SYNC_STARTUP_ERROR,
     // Sync startup has completed (i.e. ProfileSyncService::IsSyncActive()
     // returns true).
     SYNC_STARTUP_COMPLETE
   };
 
   // Returns the current state of the sync service.
   static SyncServiceState GetSyncServiceState(Profile* profile);
 
   // syncer::SyncServiceObserver implementation.
-  void OnStateChanged() override;
+  void OnStateChanged(syncer::SyncService* sync) override;
 
  private:
   // Checks the current service state and notifies |observer_| if the state
   // has changed. Note that it is expected that the observer will free this
   // object, so callers should not reference this object after making this call.
   void CheckServiceState();
 
   // Profile whose ProfileSyncService we should track.
   Profile* profile_;
 
   // Weak pointer to the observer to notify.
   Observer* observer_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncStartupTracker);
 };
 
 #endif  // CHROME_BROWSER_SYNC_SYNC_STARTUP_TRACKER_H_