WebGL: optimize webgl.texSubImage2D(video) path. (Blink side)

Source/core/html/HTMLVideoElement.h

 /*
  * Copyright (C) 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 51 matching lines @@
     bool usesOverlayFullscreenVideo() const override;
 
     // Statistics
     unsigned webkitDecodedFrameCount() const;
     unsigned webkitDroppedFrameCount() const;
 
     // Used by canvas to gain raw pixel access
     void paintCurrentFrame(SkCanvas*, const IntRect&, const SkPaint*) const;
 
     // Used by WebGL to do GPU-GPU textures copy if possible.
-    bool copyVideoTextureToPlatformTexture(WebGraphicsContext3D*, Platform3DObject texture, GLenum internalFormat, GLenum type, bool premultiplyAlpha, bool flipY);
+    bool copyVideoTextureToPlatformTexture(WebGraphicsContext3D*, GLenum target, Platform3DObject texture,
+        GLenum internalFormat, GLenum type, GLint level, bool premultiplyAlpha, bool flipY);
+    bool copyVideoSubTextureToPlatformTexture(WebGraphicsContext3D*, GLenum target, Platform3DObject texture,
+        GLint level, GLint xoffset, GLint yoffset, bool premultiplyAlpha, bool flipY);
 
     bool shouldDisplayPosterImage() const { return displayMode() == Poster; }
 
     bool hasAvailableVideoFrame() const;
 
     KURL posterImageURL() const override;
 
     // CanvasImageSource implementation
     PassRefPtr<Image> getSourceImageForCanvas(SourceImageStatus*) const override;
     bool isVideoElement() const override { return true; }
@@ skipping 21 matching lines @@
     void setDisplayMode(DisplayMode) override;
 
     OwnPtrWillBeMember<HTMLImageLoader> m_imageLoader;
 
     AtomicString m_defaultPosterURL;
 };
 
 } // namespace blink
 
 #endif // HTMLVideoElement_h