webgl: optimize webgl.texSubImage2D(video) path.

third_party/WebKit/public/platform/WebMediaPlayer.h

Index: third_party/WebKit/public/platform/WebMediaPlayer.h
diff --git a/third_party/WebKit/public/platform/WebMediaPlayer.h b/third_party/WebKit/public/platform/WebMediaPlayer.h
index 9670be708b07fb7e817505c80246021d29f37898..8f8e363f550756253713ff66b88fb611726de44c 100644
--- a/third_party/WebKit/public/platform/WebMediaPlayer.h
+++ b/third_party/WebKit/public/platform/WebMediaPlayer.h
@@ -164,17 +164,33 @@ public:
 
     virtual void paint(WebCanvas*, const WebRect&, unsigned char alpha, SkXfermode::Mode) = 0;
 
-    // TODO(dshwang): remove non-|target| version. crbug.com/349871
-    virtual bool copyVideoTextureToPlatformTexture(WebGraphicsContext3D*, unsigned texture, unsigned internalFormat, unsigned type, bool premultiplyAlpha, bool flipY) { return false; }
-
     // Do a GPU-GPU textures copy. If the copy is impossible or fails, it returns false.
-    virtual bool copyVideoTextureToPlatformTexture(WebGraphicsContext3D*, unsigned target,
-        unsigned texture, unsigned internalFormat, unsigned type, int level,
-        bool premultiplyAlpha, bool flipY) { return false; }
-    // Copy sub video frame texture to |texture|. If the copy is impossible or fails, it returns false.
-    virtual bool copyVideoSubTextureToPlatformTexture(WebGraphicsContext3D*, unsigned target,
-        unsigned texture, int level, int xoffset, int yoffset, bool premultiplyAlpha,
-        bool flipY) { return false; }
+    // Copy the video frame texture to full texture or sub texture depending on |copyType|.
+    // If FullCopy, |xoffset| and |yoffset| must be 0.
+    // If SubCopy, |internalFormat| and |type| must be GL_FALSE.
+    struct CopyVideoTextureParams {
+        enum CopyType { FullCopy, SubCopy };
+        CopyVideoTextureParams() = delete;

[philipj_slow, 2015/10/27 16:02:17]

Is this actually needed, doesn't declaring a constructor with arguments
implicitly get rid of the default constructor?

[dshwang, 2015/10/27 16:18:01]

good point. it's not needed. I removed it in the next patch set as well as in
chromium side struct.

+        CopyVideoTextureParams(CopyType copyType, unsigned target,
+            unsigned texture, unsigned internalFormat, unsigned type, int level,
+            int xoffset, int yoffset, bool premultiplyAlpha, bool flipY)
+            : copyType(copyType), target(target), texture(texture)
+            , internalFormat(internalFormat) , type(type), level(level)
+            , xoffset(xoffset), yoffset(yoffset)
+            , premultiplyAlpha(premultiplyAlpha), flipY(flipY)
+        { }
+        CopyType copyType;
+        unsigned target;
+        unsigned texture;
+        unsigned internalFormat;
+        unsigned type;
+        int level;
+        int xoffset;
+        int yoffset;
+        bool premultiplyAlpha;
+        bool flipY;
+    };
+    virtual bool copyVideoTextureToPlatformTexture(WebGraphicsContext3D*, const CopyVideoTextureParams&) = 0;
 
     virtual WebAudioSourceProvider* audioSourceProvider() { return nullptr; }