Add workspace to desktop

ui/aura_shell/desktop_background_view.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 "ui/aura_shell/desktop_background_view.h"
 
 #include "base/utf_string_conversions.h"
 #include "grit/ui_resources.h"
 #include "ui/aura/desktop.h"
 #include "ui/aura_shell/aura_shell_export.h"
@@ skipping 22 matching lines @@
 
 void DesktopBackgroundView::OnPaint(gfx::Canvas* canvas) {
   canvas->TileImageInt(wallpaper_, 0, 0, width(), height());
 }
 
 bool DesktopBackgroundView::OnMousePressed(const views::MouseEvent& event) {
   return true;
 }
 
 void DesktopBackgroundView::OnMouseReleased(const views::MouseEvent& event) {
-  Shell::GetInstance()->TileWindows();
+  Shell::GetInstance()->ToggleOverview();
 }
 
 views::Widget* CreateDesktopBackground() {
   views::Widget* desktop_widget = new views::Widget;
   views::Widget::InitParams params(views::Widget::InitParams::TYPE_CONTROL);
   params.parent = Shell::GetInstance()->GetContainer(
       aura_shell::internal::kShellWindowId_DesktopBackgroundContainer);
   DesktopBackgroundView* view = new DesktopBackgroundView;
   params.delegate = view;
   desktop_widget->Init(params);
   desktop_widget->SetContentsView(view);
   desktop_widget->Show();
   desktop_widget->GetNativeView()->set_name("DesktopBackgroundView");
   return desktop_widget;
 }
 
 }  // namespace internal
 }  // namespace aura_shell