Remove intermediate SkPicture recording from GPU tile rasterization.

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 d040bcf9a1c8d9cb78340b55ce2cd523b4860f28..c158094308f842ac7180334220d0883b6bcba2fe 100644
--- a/cc/playback/raster_source.h
+++ b/cc/playback/raster_source.h
@@ -133,15 +133,6 @@ class CC_EXPORT RasterSource : public base::RefCountedThreadSafe<RasterSource> {
     image_decode_cache_ = image_decode_cache;
   }
 
-  // Returns the ImageDecodeCache, currently only used by
-  // GpuRasterBufferProvider in order to create its own ImageHijackCanvas.
-  // Because of the MultiPictureDraw approach used by GPU raster, it does not
-  // integrate well with the use of the ImageHijackCanvas internal to this
-  // class. See gpu_raster_buffer_provider.cc for more information.
-  // TODO(crbug.com/628394): Redesign this to avoid exposing
-  // ImageDecodeCache from the raster source.
-  ImageDecodeCache* image_decode_cache() const { return image_decode_cache_; }
-
  protected:
   friend class base::RefCountedThreadSafe<RasterSource>;