[Refactor] Introduce MediaDelegate

ash/shell/shell_delegate_impl.cc

 // Copyright (c) 2012 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/shell/shell_delegate_impl.h"
 
 #include "ash/accessibility_delegate.h"
 #include "ash/caps_lock_delegate_stub.h"
 #include "ash/default_accessibility_delegate.h"
 #include "ash/default_user_wallpaper_delegate.h"
 #include "ash/host/root_window_host_factory.h"
 #include "ash/keyboard_controller_proxy_stub.h"
+#include "ash/media_delegate.h"
 #include "ash/new_window_delegate.h"
 #include "ash/session_state_delegate.h"
 #include "ash/session_state_delegate_stub.h"
 #include "ash/shell/context_menu.h"
 #include "ash/shell/example_factory.h"
 #include "ash/shell/launcher_delegate_impl.h"
 #include "ash/shell/toplevel_window.h"
 #include "ash/shell_window_ids.h"
 #include "ash/system/tray/default_system_tray_delegate.h"
 #include "ash/wm/window_state.h"
@@ skipping 21 matching lines @@
   virtual void OpenCrosh() OVERRIDE {}
   virtual void RestoreTab() OVERRIDE {}
   virtual void ShowKeyboardOverlay() OVERRIDE {}
   virtual void ShowTaskManager() OVERRIDE {}
   virtual void OpenFeedbackPage() OVERRIDE {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(NewWindowDelegateImpl);
 };
 
+class MediaDelegateImpl : public MediaDelegate {
+ public:
+  MediaDelegateImpl() {}
+  virtual ~MediaDelegateImpl() {}
+
+  virtual void HandleMediaNextTrack() OVERRIDE {}
+  virtual void HandleMediaPlayPause() OVERRIDE {}
+  virtual void HandleMediaPrevTrack() OVERRIDE {}
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(MediaDelegateImpl);
+};
+
 }  // namespace
 
 ShellDelegateImpl::ShellDelegateImpl()
     : watcher_(NULL),
       launcher_delegate_(NULL) {
 }
 
 ShellDelegateImpl::~ShellDelegateImpl() {
 }
 
@@ skipping 65 matching lines @@
 }
 
 ash::AccessibilityDelegate* ShellDelegateImpl::CreateAccessibilityDelegate() {
   return new internal::DefaultAccessibilityDelegate;
 }
 
 ash::NewWindowDelegate* ShellDelegateImpl::CreateNewWindowDelegate() {
   return new NewWindowDelegateImpl;
 }
 
+ash::MediaDelegate* ShellDelegateImpl::CreateMediaDelegate() {
+  return new MediaDelegateImpl;
+}
+
 aura::client::UserActionClient* ShellDelegateImpl::CreateUserActionClient() {
   return NULL;
 }
 
 void ShellDelegateImpl::RecordUserMetricsAction(UserMetricsAction action) {
 }
 
-void ShellDelegateImpl::HandleMediaNextTrack() {
-}
-
-void ShellDelegateImpl::HandleMediaPlayPause() {
-}
-
-void ShellDelegateImpl::HandleMediaPrevTrack() {
-}
-
 ui::MenuModel* ShellDelegateImpl::CreateContextMenu(aura::Window* root) {
   return new ContextMenu(root);
 }
 
 RootWindowHostFactory* ShellDelegateImpl::CreateRootWindowHostFactory() {
   return RootWindowHostFactory::Create();
 }
 
 base::string16 ShellDelegateImpl::GetProductName() const {
   return base::string16();
 }
 
 }  // namespace shell
 }  // namespace ash