[Aura] Refactor and update app list window.

ui/aura_shell/shell.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/shell.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "ui/aura/aura_switches.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/drag_drop_client.h"
 #include "ui/aura/desktop.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_types.h"
+#include "ui/aura_shell/app_list.h"
 #include "ui/aura_shell/default_container_event_filter.h"
 #include "ui/aura_shell/default_container_layout_manager.h"
 #include "ui/aura_shell/desktop_event_filter.h"
 #include "ui/aura_shell/desktop_layout_manager.h"
 #include "ui/aura_shell/drag_drop_controller.h"
 #include "ui/aura_shell/launcher/launcher.h"
 #include "ui/aura_shell/modal_container_layout_manager.h"
 #include "ui/aura_shell/shelf_layout_controller.h"
 #include "ui/aura_shell/shell_delegate.h"
 #include "ui/aura_shell/shell_factory.h"
@@ skipping 185 matching lines @@
 void Shell::RemoveDesktopEventFilter(aura::EventFilter* filter) {
   static_cast<internal::DesktopEventFilter*>(
       aura::Desktop::GetInstance()->event_filter())->RemoveFilter(filter);
 }
 
 void Shell::ToggleOverview() {
   if (workspace_controller_.get())
     workspace_controller_->ToggleOverview();
 }
 
+void Shell::ToggleAppList() {
+  if (!app_list_.get())
+    app_list_.reset(new internal::AppList);
+  app_list_->SetVisible(!app_list_->IsVisible());
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // Shell, private:
 
 void Shell::EnableWorkspaceManager() {
   aura::Window* default_container =
       GetContainer(internal::kShellWindowId_DefaultContainer);
 
   workspace_controller_.reset(
       new internal::WorkspaceController(default_container));
   workspace_controller_->SetLauncherModel(launcher_->model());
   default_container->SetEventFilter(
       new internal::DefaultContainerEventFilter(default_container));
   default_container->SetLayoutManager(
       new internal::DefaultContainerLayoutManager(
           workspace_controller_->workspace_manager()));
 }
 
 }  // namespace aura_shell