Remove unneeded enum forward declarations

content/renderer/media/webmediaplayer_ms.h

 // Copyright 2013 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 CONTENT_RENDERER_MEDIA_WEBMEDIAPLAYER_MS_H_
 #define CONTENT_RENDERER_MEDIA_WEBMEDIAPLAYER_MS_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 11 matching lines @@
 
 namespace blink {
 class WebFrame;
 class WebMediaPlayerClient;
 class WebSecurityOrigin;
 class WebString;
 }
 
 namespace media {
 class MediaLog;
-enum VideoRotation;
 }
 
 namespace cc_blink {
 class WebLayerImpl;
 }
 
 namespace gpu {
 namespace gles2 {
 class GLES2Interface;
 }
@@ skipping 218 matching lines @@
   // True if playback should be started upon the next call to OnShown(). Only
   // used on Android.
   bool should_play_upon_shown_;
 
   DISALLOW_COPY_AND_ASSIGN(WebMediaPlayerMS);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_WEBMEDIAPLAYER_MS_H_