Use refs for GraphicsContext

third_party/WebKit/Source/platform/scroll/ScrollbarThemeMacNonOverlayAPI.mm

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 130 matching lines @@
     // The ends are rounded and the thumb doesn't go there.
     tickmarkTrackRect.inflateY(-tickmarkTrackRect.width());
     // Inset a bit.
     tickmarkTrackRect.setX(tickmarkTrackRect.x() + 2);
     tickmarkTrackRect.setWidth(tickmarkTrackRect.width() - 5);
     paintGivenTickmarks(drawingCanvas, scrollbar, tickmarkTrackRect, tickmarks);
 
     if (!canDrawDirectly) {
         ASSERT(imageBuffer);
         if (!context.contextDisabled()) {
-            imageBuffer->draw(&context, FloatRect(scrollbar.frameRect().location(), FloatSize(imageBuffer->size())),
+            imageBuffer->draw(context, FloatRect(scrollbar.frameRect().location(), FloatSize(imageBuffer->size())),
                 nullptr, SkXfermode::kSrcOver_Mode);
         }
     }
 
     return true;
 }
 
 int ScrollbarThemeMacNonOverlayAPI::scrollbarThickness(ScrollbarControlSize controlSize)
 {
     return cScrollbarThickness[controlSize];
@@ skipping 148 matching lines @@
         return IntRect(scrollbar.x() + startWidth, scrollbar.y(), scrollbar.width() - totalWidth, thickness);
     return IntRect(scrollbar.x(), scrollbar.y() + startWidth, thickness, scrollbar.height() - totalWidth);
 }
 
 int ScrollbarThemeMacNonOverlayAPI::minimumThumbLength(const ScrollbarThemeClient& scrollbar)
 {
     return cThumbMinLength[scrollbar.controlSize()];
 }
 
 }