[Refactor] Introduce MediaDelegate

ash/shell_delegate.h

 // 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.
 
 #ifndef ASH_SHELL_DELEGATE_H_
 #define ASH_SHELL_DELEGATE_H_
 
 #include <string>
 
 #include "ash/ash_export.h"
@@ skipping 24 matching lines @@
 namespace keyboard {
 class KeyboardControllerProxy;
 }
 
 namespace ash {
 
 class CapsLockDelegate;
 class LauncherDelegate;
 class LauncherModel;
 struct LauncherItem;
+class MediaDelegate;
 class NewWindowDelegate;
 class RootWindowHostFactory;
 class AccessibilityDelegate;
 class SessionStateDelegate;
 class SystemTrayDelegate;
 class UserWallpaperDelegate;
 
 enum UserMetricsAction {
   UMA_ACCEL_KEYBOARD_BRIGHTNESS_DOWN_F6,
   UMA_ACCEL_KEYBOARD_BRIGHTNESS_UP_F7,
@@ skipping 105 matching lines @@
 
   // Creates a session state delegate. Shell takes ownership of the delegate.
   virtual SessionStateDelegate* CreateSessionStateDelegate() = 0;
 
   // Creates a accessibility delegate. Shell takes ownership of the delegate.
   virtual AccessibilityDelegate* CreateAccessibilityDelegate() = 0;
 
   // Creates an application delegate. Shell takes ownership of the delegate.
   virtual NewWindowDelegate* CreateNewWindowDelegate() = 0;
 
+  // Creates a media delegate. Shell takes ownership of the delegate.
+  virtual MediaDelegate* CreateMediaDelegate() = 0;
+
   // Creates a user action client. Shell takes ownership of the object.
   virtual aura::client::UserActionClient* CreateUserActionClient() = 0;
 
   // Records that the user performed an action.
   virtual void RecordUserMetricsAction(UserMetricsAction action) = 0;
 
-  // Handles the Next Track Media shortcut key.
-  virtual void HandleMediaNextTrack() = 0;
-
-  // Handles the Play/Pause Toggle Media shortcut key.
-  virtual void HandleMediaPlayPause() = 0;
-
-  // Handles the Previous Track Media shortcut key.
-  virtual void HandleMediaPrevTrack() = 0;
-
   // Creates a menu model of the context for the |root_window|.
   virtual ui::MenuModel* CreateContextMenu(aura::Window* root_window) = 0;
 
   // Creates a root window host factory. Shell takes ownership of the returned
   // value.
   virtual RootWindowHostFactory* CreateRootWindowHostFactory() = 0;
 
   // Get the product name.
   virtual base::string16 GetProductName() const = 0;
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELL_DELEGATE_H_