Replace more ObserverList with base::ObserverList.

chromeos/audio/cras_audio_handler.h

 // Copyright (c) 2013 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 CHROMEOS_AUDIO_CRAS_AUDIO_HANDLER_H_
 #define CHROMEOS_AUDIO_CRAS_AUDIO_HANDLER_H_
 
 #include <stdint.h>
 #include <queue>
 
@@ skipping 288 matching lines @@
     CHANGED_DEVICE,
   };
 
   // Checks if |device| is a newly discovered, changed, or existing device for
   // the nodes sent from NodesChanged signal.
   DeviceStatus CheckDeviceStatus(const AudioDevice& device);
 
   void NotifyActiveNodeChanged(bool is_input);
 
   scoped_refptr<AudioDevicesPrefHandler> audio_pref_handler_;
-  ObserverList<AudioObserver> observers_;
+  base::ObserverList<AudioObserver> observers_;
 
   // Audio data and state.
   AudioDeviceMap audio_devices_;
 
   AudioDevicePriorityQueue input_devices_pq_;
   AudioDevicePriorityQueue output_devices_pq_;
 
   bool output_mute_on_;
   bool input_mute_on_;
   int output_volume_;
   int input_gain_;
   uint64_t active_output_node_id_;
   uint64_t active_input_node_id_;
   bool has_alternative_input_;
   bool has_alternative_output_;
 
   bool output_mute_locked_;
 
   // Failures are not logged at startup, since CRAS may not be running yet.
   bool log_errors_;
 
   base::WeakPtrFactory<CrasAudioHandler> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(CrasAudioHandler);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROMEOS_AUDIO_CRAS_AUDIO_HANDLER_H_