Rename the aura_shell namespace to ash

ash/wm/shadow.cc

 // 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.
 
 #include "ash/wm/shadow.h"
 
 #include "ash/wm/image_grid.h"
 #include "grit/ui_resources.h"
 #include "ui/base/resource/resource_bundle.h"
 
-namespace aura_shell {
+namespace ash {
 namespace internal {
 
 Shadow::Shadow() {
 }
 
 Shadow::~Shadow() {
 }
 
 ui::Layer* Shadow::layer() const { return image_grid_->layer(); }
 
@@ skipping 22 matching lines @@
                     image_grid_->top_image_height() +
                     image_grid_->bottom_image_height()));
   image_grid_->layer()->SetBounds(
       gfx::Rect(content_bounds.x() - image_grid_->left_image_width(),
                 content_bounds.y() - image_grid_->top_image_height(),
                 image_grid_->layer()->bounds().width(),
                 image_grid_->layer()->bounds().height()));
 }
 
 }  // namespace internal
-}  // namespace aura_shell
+}  // namespace ash