webgl: optimize webgl.texSubImage2D(video) path.

media/blink/webmediaplayer_impl.cc

Index: media/blink/webmediaplayer_impl.cc
diff --git a/media/blink/webmediaplayer_impl.cc b/media/blink/webmediaplayer_impl.cc
index bee9dae7d4bf96ad51364d16362d77d3c4f0dd28..10e8096a5ef11b69375efe24abb0259d5a0a4eb3 100644
--- a/media/blink/webmediaplayer_impl.cc
+++ b/media/blink/webmediaplayer_impl.cc
@@ -642,12 +642,12 @@ unsigned WebMediaPlayerImpl::videoDecodedByteCount() const {
 
 bool WebMediaPlayerImpl::copyVideoTextureToPlatformTexture(
     blink::WebGraphicsContext3D* web_graphics_context,
-    unsigned int texture,
-    unsigned int internal_format,
-    unsigned int type,
-    bool premultiply_alpha,
-    bool flip_y) {
+    const CopyVideoTextureParams& params) {
   TRACE_EVENT0("media", "WebMediaPlayerImpl:copyVideoTextureToPlatformTexture");
+  DCHECK((params.copyType == CopyVideoTextureParams::FullCopy &&
+          !params.xoffset && !params.yoffset) ||
+         (params.copyType == CopyVideoTextureParams::SubCopy &&
+          !params.internalFormat && !params.type));
 
   scoped_refptr<VideoFrame> video_frame = GetCurrentFrameFromCompositor();
 
@@ -661,9 +661,15 @@ bool WebMediaPlayerImpl::copyVideoTextureToPlatformTexture(
   gpu::gles2::GLES2Interface* gl =
       static_cast<gpu_blink::WebGraphicsContext3DImpl*>(web_graphics_context)
           ->GetGLInterface();
+  typedef SkCanvasVideoRenderer::CopyFrameSingleTextureParams CopyParams;
   SkCanvasVideoRenderer::CopyVideoFrameSingleTextureToGLTexture(
-      gl, video_frame.get(), texture, internal_format, type, premultiply_alpha,
-      flip_y);
+      gl, video_frame.get(),
+      CopyParams(params.copyType == CopyVideoTextureParams::FullCopy
+                     ? CopyParams::FullCopy
+                     : CopyParams::SubCopy,
+                 params.target, params.texture, params.internalFormat,
+                 params.type, params.level, params.xoffset, params.yoffset,
+                 params.premultiplyAlpha, params.flipY));
   return true;
 }