Support reading pixels from HW-decoded video textures into canvas/webgl.

media/filters/gpu_video_decoder.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 "media/filters/gpu_video_decoder.h"
 
 #include "base/bind.h"
 #include "base/callback_helpers.h"
 #include "base/cpu.h"
 #include "base/message_loop.h"
@@ skipping 400 matching lines @@
   const PictureBuffer& pb = it->second;
 
   // Update frame's timestamp.
   base::TimeDelta timestamp;
   gfx::Size natural_size;
   GetBufferData(picture.bitstream_buffer_id(), &timestamp, &natural_size);
   DCHECK(decoder_texture_target_);
   scoped_refptr<VideoFrame> frame(VideoFrame::WrapNativeTexture(
       pb.texture_id(), decoder_texture_target_, pb.size(), natural_size,
       timestamp,
+      base::Bind(&Factories::ReadPixels, factories_, pb.texture_id(),
+                 decoder_texture_target_, pb.size()),
       base::Bind(&GpuVideoDecoder::ReusePictureBuffer, this,
                  picture.picture_buffer_id())));
 
   EnqueueFrameAndTriggerFrameDelivery(frame);
 }
 
 void GpuVideoDecoder::EnqueueFrameAndTriggerFrameDelivery(
     const scoped_refptr<VideoFrame>& frame) {
   DCHECK(gvd_loop_proxy_->BelongsToCurrentThread());
 
@@ skipping 152 matching lines @@
 
   error_occured_ = true;
 
   if (!pending_read_cb_.is_null()) {
     base::ResetAndReturn(&pending_read_cb_).Run(kDecodeError, NULL);
     return;
   }
 }
 
 }  // namespace media