Rename paint data structures

cc/blink/scrollbar_impl.h

Index: cc/blink/scrollbar_impl.h
diff --git a/cc/blink/scrollbar_impl.h b/cc/blink/scrollbar_impl.h
index 4e4bdaedc25e7a5e2e304a71280cb06c61b7ebd1..d5c3052c40728f0a909c6e5a047226d4818a3e94 100644
--- a/cc/blink/scrollbar_impl.h
+++ b/cc/blink/scrollbar_impl.h
@@ -9,6 +9,7 @@
 
 #include "base/macros.h"
 #include "cc/input/scrollbar.h"
+#include "cc/paint/paint_canvas.h"
 #include "third_party/WebKit/public/platform/WebScrollbarThemePainter.h"
 
 namespace blink {
@@ -36,7 +37,7 @@ class ScrollbarImpl : public cc::Scrollbar {
   gfx::Rect TrackRect() const override;
   float ThumbOpacity() const override;
   bool NeedsPaintPart(cc::ScrollbarPart part) const override;
-  void PaintPart(SkCanvas* canvas,
+  void PaintPart(cc::PaintCanvas* canvas,
                  cc::ScrollbarPart part,
                  const gfx::Rect& content_rect) override;