Replace more ObserverList with base::ObserverList.

ash/wm/video_detector.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 ASH_WM_VIDEO_DETECTOR_H_
 #define ASH_WM_VIDEO_DETECTOR_H_
 
 #include <map>
 
 #include "ash/ash_export.h"
@@ skipping 70 matching lines @@
   typedef std::map<aura::Window*, linked_ptr<WindowInfo> > WindowInfoMap;
 
   // Possibly notifies observers in response to detection of a video in
   // |window|.  Notifications are rate-limited and don't get sent if the window
   // is invisible or offscreen.
   void MaybeNotifyObservers(aura::Window* window, base::TimeTicks now);
 
   // Maps from a window that we're tracking to information about it.
   WindowInfoMap window_infos_;
 
-  ObserverList<VideoDetectorObserver> observers_;
+  base::ObserverList<VideoDetectorObserver> observers_;
 
   // Last time at which we notified observers that a video was playing.
   base::TimeTicks last_observer_notification_time_;
 
   // If set, used when the current time is needed.  This can be set by tests to
   // simulate the passage of time.
   base::TimeTicks now_for_test_;
 
   ScopedObserver<aura::Window, aura::WindowObserver> observer_manager_;
 
   bool is_shutting_down_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoDetector);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_VIDEO_DETECTOR_H_