Rename the aura_shell namespace to ash

ash/app_list/drop_shadow_label.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_DROP_SHADOW_LABEL_H_
 #define ASH_APP_LIST_DROP_SHADOW_LABEL_H_
 #pragma once
 
 #include "ui/gfx/font.h"
 #include "ui/views/controls/label.h"
 
-namespace aura_shell {
+namespace ash {
 
 /////////////////////////////////////////////////////////////////////////////
 //
 // DropShadowLabel class
 //
 // A drop shadow label is a view subclass that can display a string
 // with a drop shadow.
 //
 /////////////////////////////////////////////////////////////////////////////
 class DropShadowLabel : public views::Label  {
@@ skipping 19 matching lines @@
 
  protected:
   virtual gfx::Size GetTextSize() const OVERRIDE;
 
  private:
   int drop_shadow_size_;
 
   DISALLOW_COPY_AND_ASSIGN(DropShadowLabel);
 };
 
-}  // namespace aura_shell
+}  // namespace ash
 
 #endif  // ASH_APP_LIST_DROP_SHADOW_LABEL_H_