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

content/renderer/media/android/webmediaplayer_android.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/android/webmediaplayer_android.h"
 
 #include <limits>
 
 #include "base/android/build_info.h"
 #include "base/bind.h"
@@ skipping 479 matching lines @@
     bitmap.setInfo(info);
     bitmap.setPixelRef(pixelRef)->unref();
   }
 
   return true;
 }
 
 void WebMediaPlayerAndroid::paint(blink::WebCanvas* canvas,
                                   const blink::WebRect& rect,
                                   unsigned char alpha) {
+  paint(canvas, rect, alpha, SkXfermode::kSrcOver_Mode);
+}
+
+void WebMediaPlayerAndroid::paint(blink::WebCanvas* canvas,
+                                  const blink::WebRect& rect,
+                                  unsigned char alpha,
+                                  SkXfermode::Mode mode) {
   scoped_ptr<blink::WebGraphicsContext3DProvider> provider =
     scoped_ptr<blink::WebGraphicsContext3DProvider>(blink::Platform::current(
       )->createSharedOffscreenGraphicsContext3DProvider());
   if (!provider)
     return;
   blink::WebGraphicsContext3D* context3D = provider->context3d();
   if (!context3D || !context3D->makeContextCurrent())
     return;
 
   // Copy video texture into a RGBA texture based bitmap first as video texture
@@ skipping 15 matching lines @@
   }
 
   // Draw the texture based bitmap onto the Canvas. If the canvas is
   // hardware based, this will do a GPU-GPU texture copy.
   // If the canvas is software based, the texture based bitmap will be
   // readbacked to system memory then draw onto the canvas.
   SkRect dest;
   dest.set(rect.x, rect.y, rect.x + rect.width, rect.y + rect.height);
   SkPaint paint;
   paint.setAlpha(alpha);
+  paint.setXfermodeMode(mode);
   // It is not necessary to pass the dest into the drawBitmap call since all
   // the context have been set up before calling paintCurrentFrameInContext.
   canvas->drawBitmapRect(bitmap_, 0, dest, &paint);
 }
 
 bool WebMediaPlayerAndroid::copyVideoTextureToPlatformTexture(
     blink::WebGraphicsContext3D* web_graphics_context,
     unsigned int texture,
     unsigned int level,
     unsigned int internal_format,
@@ skipping 1075 matching lines @@
     player_manager_->EnterFullscreen(player_id_, frame_);
     SetNeedsEstablishPeer(false);
   }
 }
 
 bool WebMediaPlayerAndroid::canEnterFullscreen() const {
   return player_manager_->CanEnterFullscreen(frame_);
 }
 
 }  // namespace content