cc: Support texcoord offsets in YUVVideoDrawQuad

cc/layers/video_layer_impl.cc

Index: cc/layers/video_layer_impl.cc
diff --git a/cc/layers/video_layer_impl.cc b/cc/layers/video_layer_impl.cc
index 6bc4b2f82c07a11445e3dd179a6893f4e62b37f9..cf71c3c6b532317e081b03cd83e6b83ef7fef5a5 100644
--- a/cc/layers/video_layer_impl.cc
+++ b/cc/layers/video_layer_impl.cc
@@ -139,10 +139,14 @@ void VideoLayerImpl::AppendQuads(QuadSink* quad_sink,
   gfx::Size coded_size = frame_->coded_size();
 
   // Pixels for macroblocked formats.
-  float tex_width_scale =
+  const float tex_width_scale =
       static_cast<float>(visible_rect.width()) / coded_size.width();
-  float tex_height_scale =
+  const float tex_height_scale =
       static_cast<float>(visible_rect.height()) / coded_size.height();
+  const float tex_x_offset =
+      static_cast<float>(visible_rect.x()) / coded_size.width();
+  const float tex_y_offset =
+      static_cast<float>(visible_rect.y()) / coded_size.height();
 
   switch (frame_resource_type_) {
     // TODO(danakj): Remove this, hide it in the hardware path.
@@ -175,14 +179,15 @@ void VideoLayerImpl::AppendQuads(QuadSink* quad_sink,
       DCHECK_GE(frame_resources_.size(), 3u);
       if (frame_resources_.size() < 3u)
         break;
-      gfx::SizeF tex_scale(tex_width_scale, tex_height_scale);
+      gfx::RectF tex_coord_rect(
+          tex_x_offset, tex_y_offset, tex_width_scale, tex_height_scale);
       scoped_ptr<YUVVideoDrawQuad> yuv_video_quad = YUVVideoDrawQuad::Create();
       yuv_video_quad->SetNew(
           shared_quad_state,
           quad_rect,
           opaque_rect,
           visible_quad_rect,
-          tex_scale,
+          tex_coord_rect,
           frame_resources_[0],
           frame_resources_[1],
           frame_resources_[2],