Rename the aura_shell namespace to ash

ash/app_list/app_list_item_view_listener.h

 // Copyright (c) 2011 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_APP_LIST_APP_LIST_ITEM_VIEW_LISTENER_H_
 #define ASH_APP_LIST_APP_LIST_ITEM_VIEW_LISTENER_H_
 #pragma once
 
 #include "ash/ash_export.h"
 
-namespace aura_shell {
+namespace ash {
 
 class AppListItemView;
 
 class ASH_EXPORT AppListItemViewListener {
  public:
   // Invoked when an AppListeItemModelView is activated by click or enter key.
   virtual void AppListItemActivated(AppListItemView* sender,
                                     int event_flags) = 0;
 
  protected:
   virtual ~AppListItemViewListener() {}
 };
 
-}  // namespace aura_shell
+}  // namespace ash
 
 #endif  // ASH_APP_LIST_APP_LIST_ITEM_VIEW_LISTENER_H_