media: Implement zero-copy video playback for VP8.

cc/layers/video_layer_impl.cc

 // Copyright 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.
 
 #include "cc/layers/video_layer_impl.h"
 
 #include <stddef.h>
 
 #include "base/bind.h"
 #include "base/logging.h"
@@ skipping 232 matching lines @@
         } else if (videoframe_color_space == media::COLOR_SPACE_HD_REC709) {
           color_space = YUVVideoDrawQuad::REC_709;
         }
       }
 
       const gfx::Size ya_tex_size = coded_size;
       gfx::Size uv_tex_size = media::VideoFrame::PlaneSize(
           frame_->format(), media::VideoFrame::kUPlane, coded_size);
 
       if (frame_->HasTextures()) {
-        DCHECK_EQ(media::PIXEL_FORMAT_I420, frame_->format());
-        DCHECK_EQ(3u, frame_resources_.size());  // Alpha is not supported yet.
+        if (DCHECK_IS_ON()) {
+          if (frame_->format() == media::PIXEL_FORMAT_I420) {
+            DCHECK_EQ(3u, frame_resources_.size());
+          } else if (frame_->format() == media::PIXEL_FORMAT_YV12A) {
+            DCHECK_EQ(4u, frame_resources_.size());
+          } else {
+            NOTREACHED();
+          }
+        }
       } else {
         DCHECK(uv_tex_size ==
                media::VideoFrame::PlaneSize(
                    frame_->format(), media::VideoFrame::kVPlane, coded_size));
         DCHECK(frame_resources_.size() <= 3 ||
                ya_tex_size == media::VideoFrame::PlaneSize(
                                   frame_->format(), media::VideoFrame::kAPlane,
                                   coded_size));
       }
 
@@ skipping 147 matching lines @@
 void VideoLayerImpl::SetNeedsRedraw() {
   SetUpdateRect(gfx::UnionRects(update_rect(), gfx::Rect(bounds())));
   layer_tree_impl()->SetNeedsRedraw();
 }
 
 const char* VideoLayerImpl::LayerTypeAsString() const {
   return "cc::VideoLayerImpl";
 }
 
 }  // namespace cc