Make rendering use PaintingNodes for increased efficiency.

sky/engine/platform/graphics/DecodingImageGenerator.h

Index: sky/engine/platform/graphics/DecodingImageGenerator.h
diff --git a/sky/engine/platform/graphics/DecodingImageGenerator.h b/sky/engine/platform/graphics/DecodingImageGenerator.h
index a2e948e51856bf003730a9ccb4344e37940a420e..fb2d21eb398593bda534ba643276d96f77860bf7 100644
--- a/sky/engine/platform/graphics/DecodingImageGenerator.h
+++ b/sky/engine/platform/graphics/DecodingImageGenerator.h
@@ -40,7 +40,7 @@ class ImageFrameGenerator;
 // memory with decoded pixels.
 //
 // This class does not own an ImageDecode. It does not own encoded data. It serves
-// as and adapter to ImageFrameGenerator which actually performs decoding.
+// as an adapter to ImageFrameGenerator which actually performs decoding.
 class DecodingImageGenerator final : public SkImageGenerator {
 public:
     DecodingImageGenerator(PassRefPtr<ImageFrameGenerator>, const SkImageInfo&, size_t index);