Cleanup: Remove unneeded forward declarations in webkit/plugins/.

webkit/plugins/ppapi/ppb_video_decoder_impl.h

 // 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.
 
 #ifndef WEBKIT_PLUGINS_PPAPI_PPB_VIDEO_DECODER_IMPL_H_
 #define WEBKIT_PLUGINS_PPAPI_PPB_VIDEO_DECODER_IMPL_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 11 matching lines @@
 struct PP_VideoBitstreamBuffer_Dev;
 struct PPB_VideoDecoder_Dev;
 struct PPP_VideoDecoder_Dev;
 
 namespace gpu {
 namespace gles2 {
 class GLES2Implementation;
 }  // namespace gles2
 }  // namespace gpu
 
-namespace ppapi {
-namespace thunk {
-class PPB_Context3D_API;
-}  // namespace thunk
-}  // namespace ppapi
-
-
 namespace webkit {
 namespace ppapi {
 
 class PPB_VideoDecoder_Impl : public ::ppapi::Resource,
                               public ::ppapi::VideoDecoderImpl,
                               public media::VideoDecodeAccelerator::Client {
  public:
   virtual ~PPB_VideoDecoder_Impl();
   // See PPB_VideoDecoder_Dev::Create.  Returns 0 on failure to create &
   // initialize.
@@ skipping 41 matching lines @@
   // Reference to the plugin requesting this interface.
   const PPP_VideoDecoder_Dev* ppp_videodecoder_;
 
   DISALLOW_COPY_AND_ASSIGN(PPB_VideoDecoder_Impl);
 };
 
 }  // namespace ppapi
 }  // namespace webkit
 
 #endif  // WEBKIT_PLUGINS_PPAPI_PPB_VIDEO_DECODER_IMPL_H_