Replace more ObserverList with base::ObserverList.

ash/shelf/shelf_button.cc

 // Copyright 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.
 
 #include "ash/shelf/shelf_button.h"
 
 #include <algorithm>
 
 #include "ash/ash_constants.h"
 #include "ash/ash_switches.h"
@@ skipping 80 matching lines @@
   // gfx::AnimationDelegate
   void AnimationProgressed(const gfx::Animation* animation) override {
     if (animation != &animation_)
       return;
     if (!animation_.is_animating())
       return;
     FOR_EACH_OBSERVER(Observer, observers_, AnimationProgressed());
   }
 
   gfx::ThrobAnimation animation_;
-  ObserverList<Observer> observers_;
+  base::ObserverList<Observer> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(ShelfButtonAnimation);
 };
 
 }  // namespace
 
 namespace ash {
 
 ////////////////////////////////////////////////////////////////////////////////
 // ShelfButton::BarView
@@ skipping 434 matching lines @@
             views::ImageView::CENTER,
             views::ImageView::CENTER,
             views::ImageView::LEADING));
     bar_->SchedulePaint();
   }
 
   bar_->SetVisible(bar_id != 0 && state_ != STATE_NORMAL);
 }
 
 }  // namespace ash