Remove NOTIFICATION_SYSTEM_SETTING_CHANGED, switch CrosSettings to base::CallbackRegistry.

chrome/browser/chromeos/login/user_manager_impl.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_LOGIN_USER_MANAGER_IMPL_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USER_MANAGER_IMPL_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 380 matching lines @@
   // access.
   FlowMap specific_flows_;
 
   // User sessions that have to be restored after browser crash.
   // [user_id] > [user_id_hash]
   SessionManagerClient::ActiveSessionsMap pending_user_sessions_;
 
   // Time at which this object was created.
   base::TimeTicks manager_creation_time_;
 
+  scoped_ptr<CrosSettings::ObserverSubscription>
+      local_accounts_subscription_;
+  scoped_ptr<CrosSettings::ObserverSubscription>
+      supervised_users_subscription_;
+
   DISALLOW_COPY_AND_ASSIGN(UserManagerImpl);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USER_MANAGER_IMPL_H_