Adding YUVA support for enabling Alpha Playback

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 "base/bind.h"
 #include "base/logging.h"
 #include "cc/layers/quad_sink.h"
 #include "cc/layers/video_frame_provider_client_impl.h"
@@ skipping 155 matching lines @@
                            software_resources_[0],
                            premultiplied_alpha,
                            uv_top_left,
                            uv_bottom_right,
                            opacity,
                            flipped);
       quad_sink->Append(texture_quad.PassAs<DrawQuad>(), append_quads_data);
       break;
     }
     case VideoFrameExternalResources::YUV_RESOURCE: {
-      DCHECK_EQ(frame_resources_.size(), 3u);
+      DCHECK_GE(frame_resources_.size(), 3u);
       if (frame_resources_.size() < 3u)
         break;
       gfx::SizeF tex_scale(tex_width_scale, tex_height_scale);
       scoped_ptr<YUVVideoDrawQuad> yuv_video_quad = YUVVideoDrawQuad::Create();
       yuv_video_quad->SetNew(shared_quad_state,
                              quad_rect,
                              opaque_rect,
                              tex_scale,
                              frame_resources_[0],
                              frame_resources_[1],
-                             frame_resources_[2]);
+                             frame_resources_[2],
+                             frame_resources_.size() > 3 ?
+                                 frame_resources_[3] : 0);
       quad_sink->Append(yuv_video_quad.PassAs<DrawQuad>(), append_quads_data);
       break;
     }
     case VideoFrameExternalResources::RGB_RESOURCE: {
       if (!hardware_resource_) {
         DCHECK_EQ(frame_resources_.size(), 1u);
         if (frame_resources_.size() < 1u)
           break;
       }
       bool premultiplied_alpha = true;
@@ skipping 124 matching lines @@
 void VideoLayerImpl::SetProviderClientImpl(
     scoped_refptr<VideoFrameProviderClientImpl> provider_client_impl) {
   provider_client_impl_ = provider_client_impl;
 }
 
 const char* VideoLayerImpl::LayerTypeAsString() const {
   return "cc::VideoLayerImpl";
 }
 
 }  // namespace cc