2D Canvas doesn't blend video with the destination buffer.

content/renderer/media/webmediaplayer_impl.cc

 // Copyright 2013 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 "content/renderer/media/webmediaplayer_impl.h"
 
 #include <algorithm>
 #include <limits>
 #include <string>
 #include <vector>
@@ skipping 513 matching lines @@
   return duration();
 }
 
 bool WebMediaPlayerImpl::didLoadingProgress() {
   DCHECK(main_loop_->BelongsToCurrentThread());
   bool pipeline_progress = pipeline_.DidLoadingProgress();
   bool data_progress = buffered_data_source_host_.DidLoadingProgress();
   return pipeline_progress || data_progress;
 }
 
-void WebMediaPlayerImpl::paint(WebCanvas* canvas,
-                               const WebRect& rect,
+void WebMediaPlayerImpl::paint(blink::WebCanvas* canvas,
+                               const blink::WebRect& rect,
                                unsigned char alpha) {
+  paint(canvas, rect, alpha, SkXfermode::kSrcOver_Mode);
+}
+
+void WebMediaPlayerImpl::paint(blink::WebCanvas* canvas,
+                               const blink::WebRect& rect,
+                               unsigned char alpha,
+                               SkXfermode::Mode mode) {
   DCHECK(main_loop_->BelongsToCurrentThread());
   TRACE_EVENT0("media", "WebMediaPlayerImpl:paint");
 
   // TODO(scherkus): Clarify paint() API contract to better understand when and
   // why it's being called. For example, today paint() is called when:
   //   - We haven't reached HAVE_CURRENT_DATA and need to paint black
   //   - We're painting to a canvas
   // See http://crbug.com/341225 http://crbug.com/342621 for details.
   scoped_refptr<media::VideoFrame> video_frame =
       GetCurrentFrameFromCompositor();
 
   gfx::Rect gfx_rect(rect);
 
   skcanvas_video_renderer_.Paint(video_frame.get(),
                                  canvas,
                                  gfx_rect,
                                  alpha,
+                                 mode,
                                  pipeline_metadata_.video_rotation);
 }
 
 bool WebMediaPlayerImpl::hasSingleSecurityOrigin() const {
   if (data_source_)
     return data_source_->HasSingleOrigin();
   return true;
 }
 
 bool WebMediaPlayerImpl::didPassCORSAccessCheck() const {
@@ skipping 773 matching lines @@
   compositor_task_runner_->PostTask(FROM_HERE,
                                     base::Bind(&GetCurrentFrameAndSignal,
                                                base::Unretained(compositor_),
                                                &video_frame,
                                                &event));
   event.Wait();
   return video_frame;
 }
 
 }  // namespace content