webgl: optimize webgl.texSubImage2D(video) path.

content/renderer/media/webmediaplayer_ms.cc

Index: content/renderer/media/webmediaplayer_ms.cc
diff --git a/content/renderer/media/webmediaplayer_ms.cc b/content/renderer/media/webmediaplayer_ms.cc
index 162ccf73a406758a7b7ede464df285168e8090ea..7724ed0fce80234e362fdd9d4512c32327eb983f 100644
--- a/content/renderer/media/webmediaplayer_ms.cc
+++ b/content/renderer/media/webmediaplayer_ms.cc
@@ -348,13 +348,13 @@ unsigned WebMediaPlayerMS::videoDecodedByteCount() const {
 
 bool WebMediaPlayerMS::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", "WebMediaPlayerMS:copyVideoTextureToPlatformTexture");
   DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK((params.copyType == CopyVideoTextureParams::FullCopy &&
+          !params.xoffset && !params.yoffset) ||
+         (params.copyType == CopyVideoTextureParams::SubCopy &&
+          !params.internalFormat && !params.type));
 
   scoped_refptr<media::VideoFrame> video_frame = compositor_->GetCurrentFrame();
 
@@ -369,8 +369,15 @@ bool WebMediaPlayerMS::copyVideoTextureToPlatformTexture(
       static_cast<gpu_blink::WebGraphicsContext3DImpl*>(web_graphics_context)
           ->GetGLInterface();
   media::SkCanvasVideoRenderer::CopyVideoFrameSingleTextureToGLTexture(
-      gl, video_frame.get(), texture, internal_format, type, premultiply_alpha,
-      flip_y);
+      gl, video_frame.get(),
+      {params.copyType == CopyVideoTextureParams::FullCopy

[DaleCurtis, 2015/10/21 18:35:50]

Ditto.

+           ? media::SkCanvasVideoRenderer::CopyFrameSingleTextureParams::
+                 FullCopy
+           : media::SkCanvasVideoRenderer::CopyFrameSingleTextureParams::
+                 SubCopy,
+       params.target, params.texture, params.internalFormat, params.type,
+       params.level, params.xoffset, params.yoffset, params.premultiplyAlpha,
+       params.flipY});
   return true;
 }