[Aura] Refactor and update app list window.

ui/aura_shell/launcher/launcher_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/launcher/launcher_view.h"
 
 #include "base/utf_string_conversions.h"
 #include "grit/ui_resources.h"
 #include "ui/aura/window.h"
 #include "ui/aura_shell/launcher/app_launcher_button.h"
@@ skipping 580 matching lines @@
 }
 
 void LauncherView::ButtonPressed(views::Button* sender,
                                  const views::Event& event) {
   ShellDelegate* delegate = Shell::GetInstance()->delegate();
   if (!delegate)
     return;
   if (sender == new_browser_button_) {
     delegate->CreateNewWindow();
   } else if (sender == show_apps_button_) {
-    delegate->ShowApps();
+    Shell::GetInstance()->ToggleAppList();
   } else if (sender == overflow_button_) {
     ShowOverflowMenu();
   } else {
     int view_index = view_model_->GetIndexOfView(sender);
     // May be -1 while in the process of animating closed.
     if (view_index != -1)
       delegate->LauncherItemClicked(model_->items()[view_index]);
   }
 }
 
 }  // namespace internal
 }  // namespace aura_shell