cc: Partial tile update for one-copy raster.

cc/playback/raster_source.h

Index: cc/playback/raster_source.h
diff --git a/cc/playback/raster_source.h b/cc/playback/raster_source.h
index c0a484aa8d9a28d312bd8353cbeb402aa7c5d169..8d0356fae3807ecf5abb2331cd3a33d1b7a95284 100644
--- a/cc/playback/raster_source.h
+++ b/cc/playback/raster_source.h
@@ -41,7 +41,8 @@ class CC_EXPORT RasterSource : public base::RefCountedThreadSafe<RasterSource> {
   // It is assumed that the canvas passed here will only be rasterized by
   // this raster source via this call.
   virtual void PlaybackToCanvas(SkCanvas* canvas,
-                                const gfx::Rect& canvas_rect,
+                                const gfx::Rect& canvas_bitmap_rect,
+                                const gfx::Rect& canvas_playback_rect,

[reveman, 2015/05/22 17:15:13]

nit: same here. maybe canvas_rect and playback_rect if not it's not always
backed by a bitmap

                                 float contents_scale) const = 0;
 
   // Similar to above, except that the canvas passed here can (or was already)