Add shutdown notification and service refs to SyncServiceObserver.

chrome/browser/chromeos/login/signin/auth_sync_observer.h

 // Copyright 2014 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_CHROMEOS_LOGIN_SIGNIN_AUTH_SYNC_OBSERVER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_SIGNIN_AUTH_SYNC_OBSERVER_H_
 
 #include <string>
 
 #include "base/compiler_specific.h"
@@ skipping 15 matching lines @@
 
   void StartObserving();
 
  private:
   friend class AuthSyncObserverFactory;
 
   // KeyedService implementation.
   void Shutdown() override;
 
   // syncer::SyncServiceObserver implementation.
-  void OnStateChanged() override;
+  void OnStateChanged(syncer::SyncService* sync) override;
 
   // Called on attempt to restore supervised user token.
   void OnSupervisedTokenLoaded(const std::string& token);
 
   Profile* profile_;
 
   DISALLOW_COPY_AND_ASSIGN(AuthSyncObserver);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_SIGNIN_AUTH_SYNC_OBSERVER_H_