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

Source/core/html/HTMLVideoElement.cpp

Index: Source/core/html/HTMLVideoElement.cpp
diff --git a/Source/core/html/HTMLVideoElement.cpp b/Source/core/html/HTMLVideoElement.cpp
index e64a10fd0aa63fa70bd7c1a0daedc0f29a5d553a..32be735be660d39aef8bea234be034e3466b1d8b 100644
--- a/Source/core/html/HTMLVideoElement.cpp
+++ b/Source/core/html/HTMLVideoElement.cpp
@@ -206,13 +206,25 @@ void HTMLVideoElement::paintCurrentFrame(SkCanvas* canvas, const IntRect& destRe
     webMediaPlayer()->paint(canvas, destRect, paint ? paint->getAlpha() : 0xFF, mode);
 }
 
-bool HTMLVideoElement::copyVideoTextureToPlatformTexture(WebGraphicsContext3D* context, Platform3DObject texture, GLenum internalFormat, GLenum type, bool premultiplyAlpha, bool flipY)
+bool HTMLVideoElement::copyVideoTextureToPlatformTexture(WebGraphicsContext3D* context, GLenum target,
+    Platform3DObject texture, GLenum internalFormat, GLenum type, GLint level, bool premultiplyAlpha, bool flipY)
 {
     if (!webMediaPlayer())
         return false;
 
-    ASSERT(Extensions3DUtil::canUseCopyTextureCHROMIUM(GL_TEXTURE_2D, internalFormat, type, 0));
-    return webMediaPlayer()->copyVideoTextureToPlatformTexture(context, texture, internalFormat, type, premultiplyAlpha, flipY);
+    ASSERT(Extensions3DUtil::canUseCopyTextureCHROMIUM(target, internalFormat, type, level));
+    return webMediaPlayer()->copyVideoTextureToPlatformTexture(context, target, texture, internalFormat, type, level, premultiplyAlpha, flipY);
+}
+
+bool HTMLVideoElement::copyVideoSubTextureToPlatformTexture(WebGraphicsContext3D* context, GLenum target,
+    Platform3DObject texture, GLint level, GLint xoffset, GLint yoffset, bool premultiplyAlpha, bool flipY)
+{
+    if (!webMediaPlayer())
+        return false;
+
+    ASSERT(Extensions3DUtil::canUseCopyTextureCHROMIUM(target, GL_RGBA, GL_UNSIGNED_BYTE, level));
+    return webMediaPlayer()->copyVideoSubTextureToPlatformTexture(context, target, texture, level,
+        xoffset, yoffset, premultiplyAlpha, flipY);
 }
 
 bool HTMLVideoElement::hasAvailableVideoFrame() const