Rename the aura_shell namespace to ash

ash/wm/default_container_event_filter.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_WM_DEFAULT_CONTAINER_EVENT_FILTER_H_
 #define ASH_WM_DEFAULT_CONTAINER_EVENT_FILTER_H_
 #pragma once
 
 #include "ash/wm/toplevel_window_event_filter.h"
 
 namespace aura {
 class MouseEvent;
 class Window;
 }
 
-namespace aura_shell {
+namespace ash {
 namespace internal {
 
 class DefaultContainerEventFilter : public ToplevelWindowEventFilter {
  public:
   explicit DefaultContainerEventFilter(aura::Window* owner);
   virtual ~DefaultContainerEventFilter();
 
   // Overridden from ToplevelWindowEventFilter:
   virtual bool PreHandleMouseEvent(aura::Window* target,
                                    aura::MouseEvent* event) OVERRIDE;
@@ skipping 16 matching lines @@
   void UpdateHoveredWindow(aura::Window* toplevel);
 
   DragState drag_state_;
   // Top-level window under the mouse cursor.
   aura::Window* hovered_window_;
 
   DISALLOW_COPY_AND_ASSIGN(DefaultContainerEventFilter);
 };
 
 }  // namespace internal
-}  // namespace aura_shell
+}  // namespace ash
 
 #endif  //  ASH_WM_DEFAULT_CONTAINER_EVENT_FILTER_H_