chromeos: Replace user image notifications with observer

chrome/browser/chromeos/login/users/avatar/user_image_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_USERS_AVATAR_USER_IMAGE_SYNC_OBSERVER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_USERS_AVATAR_USER_IMAGE_SYNC_OBSERVER_H_
 
 #include <memory>
 #include <string>
 
 #include "base/observer_list.h"
 #include "components/sync_preferences/pref_service_syncable_observer.h"
+#include "components/user_manager/user_manager.h"
 #include "content/public/browser/notification_observer.h"
 
 class PrefChangeRegistrar;
 class Profile;
 
 namespace content {
 class NotificationRegistrar;
 }
 
 namespace sync_preferences {
 class PrefServiceSyncable;
 }
 
 namespace user_prefs {
 class PrefRegistrySyncable;
 }
 
 namespace user_manager {
 class User;
 }
 
 namespace chromeos {
 
 // This class is responsible for keeping local user image synced with
 // image saved in syncable preference.
 class UserImageSyncObserver
     : public sync_preferences::PrefServiceSyncableObserver,
-      public content::NotificationObserver {
+      public content::NotificationObserver,
+      public user_manager::UserManager::Observer {
  public:
   class Observer {
    public:
     // Called right after image info synced (i.e. |is_synced| became |true|).
     // |local_image_updated| indicates if we desided to update local image in
     // result of sync.
     virtual void OnInitialSync(bool local_image_updated) = 0;
     virtual ~Observer();
   };
 
@@ skipping 14 matching lines @@
 
  private:
   // sync_preferences::PrefServiceSyncableObserver implementation.
   void OnIsSyncingChanged() override;
 
   // content::NotificationObserver implementation.
   void Observe(int type,
                const content::NotificationSource& source,
                const content::NotificationDetails& details) override;
 
+  // user_manager::UserManager::Observer implementation.
+  void OnUserImageChanged(const user_manager::User& user) override;
+
   // Called after user profile was loaded.
   void OnProfileGained(Profile* profile);
 
   // Called when sync servise started it's work and we are able to sync needed
   // preferences.
   void OnInitialSync();
 
   // Called when preference |pref_name| was changed.j
   void OnPreferenceChanged(const std::string& pref_name);
 
@@ skipping 16 matching lines @@
   bool is_synced_;
   // Indicates if local user image changed during initialization.
   bool local_image_changed_;
   base::ObserverList<Observer> observer_list_;
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_USERS_AVATAR_USER_IMAGE_SYNC_OBSERVER_H_