Replace more ObserverList with base::ObserverList.

components/sync_driver/device_info_sync_service.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 COMPONENTS_SYNC_DRIVER_DEVICE_INFO_SYNC_SERVICE_H_
 #define COMPONENTS_SYNC_DRIVER_DEVICE_INFO_SYNC_SERVICE_H_
 
 #include "base/observer_list.h"
 #include "components/sync_driver/device_info_tracker.h"
 #include "sync/api/sync_change_processor.h"
@@ skipping 80 matching lines @@
   // Receives ownership of |sync_processor_| and |error_handler_| in
   // MergeDataAndStartSyncing() and destroy them in StopSyncing().
   scoped_ptr<syncer::SyncChangeProcessor> sync_processor_;
   scoped_ptr<syncer::SyncErrorFactory> error_handler_;
 
   // Cache of all syncable and local data.
   typedef std::map<std::string, syncer::SyncData> SyncDataMap;
   SyncDataMap all_data_;
 
   // Registered observers, not owned.
-  ObserverList<Observer, true> observers_;
+  base::ObserverList<Observer, true> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(DeviceInfoSyncService);
 };
 
 }  // namespace sync_driver
 
 #endif  // COMPONENTS_SYNC_DRIVER_DEVICE_INFO_SYNC_SERVICE_H_