Replace more ObserverList with base::ObserverList.

ash/shelf/shelf_layout_manager.h

 // Copyright 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_SHELF_SHELF_LAYOUT_MANAGER_H_
 #define ASH_SHELF_SHELF_LAYOUT_MANAGER_H_
 
 #include <vector>
 
 #include "ash/ash_export.h"
@@ skipping 358 matching lines @@
   // False when neither the auto hide timer nor the timer task are running.
   bool mouse_over_shelf_when_auto_hide_timer_started_;
 
   // EventFilter used to detect when user moves the mouse over the shelf to
   // trigger showing the shelf.
   scoped_ptr<AutoHideEventFilter> auto_hide_event_filter_;
 
   // EventFilter used to detect when user issues a gesture on a bezel sensor.
   scoped_ptr<ShelfBezelEventFilter> bezel_event_filter_;
 
-  ObserverList<ShelfLayoutManagerObserver> observers_;
+  base::ObserverList<ShelfLayoutManagerObserver> observers_;
 
   // The shelf reacts to gesture-drags, and can be set to auto-hide for certain
   // gestures. Some shelf behaviour (e.g. visibility state, background color
   // etc.) are affected by various stages of the drag. The enum keeps track of
   // the present status of the gesture drag.
   enum GestureDragStatus {
     GESTURE_DRAG_NONE,
     GESTURE_DRAG_IN_PROGRESS,
     GESTURE_DRAG_CANCEL_IN_PROGRESS,
     GESTURE_DRAG_COMPLETE_IN_PROGRESS
@@ skipping 22 matching lines @@
 
   // The show hide animation duration override or 0 for default.
   int duration_override_in_ms_;
 
   DISALLOW_COPY_AND_ASSIGN(ShelfLayoutManager);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELF_SHELF_LAYOUT_MANAGER_H_