gdata: Make WeakPtrFactory the last parameter

chrome/browser/chromeos/gdata/gdata_auth_service.h

 // Copyright (c) 2012 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_GDATA_GDATA_AUTH_SERVICE_H_
 #define CHROME_BROWSER_CHROMEOS_GDATA_GDATA_AUTH_SERVICE_H_
 
 #include <string>
 
 #include "base/memory/ref_counted.h"
@@ skipping 80 matching lines @@
       GDataOperationRegistry* registry,
       scoped_refptr<base::MessageLoopProxy> relay_proxy,
       const AuthStatusCallback& callback);
 
   Profile* profile_;
   std::string refresh_token_;
   std::string access_token_;
   ObserverList<Observer> observers_;
 
   content::NotificationRegistrar registrar_;
+
+  // Note: This should remain the last member so it'll be destroyed and
+  // invalidate its weak pointers before any other members are destroyed.
   base::WeakPtrFactory<GDataAuthService> weak_ptr_factory_;
-  base::WeakPtr<GDataAuthService> weak_ptr_bound_to_ui_thread_;
 
   DISALLOW_COPY_AND_ASSIGN(GDataAuthService);
 };
 
 }  // namespace gdata
 
 #endif  // CHROME_BROWSER_CHROMEOS_GDATA_GDATA_AUTH_SERVICE_H_