[Aura] Refactor and update app list window.

ui/aura_shell/shell.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 UI_AURA_SHELL_SHELL_H_
 #define UI_AURA_SHELL_SHELL_H_
 #pragma once
 
 #include <utility>
 #include <vector>
@@ skipping 12 matching lines @@
 namespace gfx {
 class Rect;
 }
 
 namespace aura_shell {
 
 class Launcher;
 class ShellDelegate;
 
 namespace internal {
+class AppList;
 class DragDropController;
 class ShelfLayoutController;
 class WorkspaceController;
 }
 
 // Shell is a singleton object that presents the Shell API and implements the
 // Desktop's delegate interface.
 class AURA_SHELL_EXPORT Shell {
  public:
   // Upon creation, the Shell sets itself as the Desktop's delegate, which takes
@@ skipping 11 matching lines @@
   aura::Window* GetContainer(int container_id);
   const aura::Window* GetContainer(int container_id) const;
 
   // Adds or removes |filter| from the DesktopEventFilter.
   void AddDesktopEventFilter(aura::EventFilter* filter);
   void RemoveDesktopEventFilter(aura::EventFilter* filter);
 
   // Toggles between overview mode and normal mode.
   void ToggleOverview();
 
+  // Toggles app list.
+  void ToggleAppList();
+
   ShellDelegate* delegate() { return delegate_.get(); }
   Launcher* launcher() { return launcher_.get(); }
 
  private:
   typedef std::pair<aura::Window*, gfx::Rect> WindowAndBoundsPair;
 
   explicit Shell(ShellDelegate* delegate);
   virtual ~Shell();
 
   void Init();
 
   // Enables WorkspaceManager.
   void EnableWorkspaceManager();
 
   static Shell* instance_;
 
   std::vector<WindowAndBoundsPair> to_restore_;
 
   base::WeakPtrFactory<Shell> method_factory_;
 
   scoped_ptr<ShellDelegate> delegate_;
 
   scoped_ptr<Launcher> launcher_;
 
+  scoped_ptr<internal::AppList> app_list_;
+
   scoped_ptr<internal::DragDropController> drag_drop_controller_;
   scoped_ptr<internal::WorkspaceController> workspace_controller_;
   scoped_ptr<internal::ShelfLayoutController> shelf_layout_controller_;
 
   DISALLOW_COPY_AND_ASSIGN(Shell);
 };
 
 }  // namespace aura_shell
 
 #endif  // UI_AURA_SHELL_SHELL_H_