media: Cleanup class/struct forward declarations

media/gpu/vaapi_tfp_picture.h

 // Copyright 2014 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.
 //
 // This file contains an implementation of picture allocation for the
 // X11 window system used by VaapiVideoDecodeAccelerator to produce
 // output pictures.
 
 #ifndef MEDIA_GPU_VAAPI_TFP_PICTURE_H_
 #define MEDIA_GPU_VAAPI_TFP_PICTURE_H_
 
 #include <stdint.h>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "media/gpu/vaapi_picture.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gl/gl_bindings.h"
 
-namespace gfx {
-class GLContextGLX;
-}
-
 namespace gl {
 class GLImageGLX;
 }
 
 namespace media {
 
 class VaapiWrapper;
 
 // Implementation of VaapiPicture for the X11 backed chromium.
 class VaapiTFPPicture : public VaapiPicture {
@@ skipping 22 matching lines @@
 
   Pixmap x_pixmap_;
   scoped_refptr<gl::GLImageGLX> glx_image_;
 
   DISALLOW_COPY_AND_ASSIGN(VaapiTFPPicture);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_GPU_VAAPI_TFP_PICTURE_H_