Make OffscreenCanvasRenderingContext2D renderable on a worker

third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2D.h

 /*
  * Copyright (C) 2006, 2007, 2009, 2010, 2011, 2012 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 144 matching lines @@
     void disableDeferral(DisableDeferralReason) final;
 
     AffineTransform baseTransform() const final;
     void didDraw(const SkIRect& dirtyRect) final;
 
     bool stateHasFilter() final;
     SkImageFilter* stateGetFilter() final;
 
     void validateStateStack() final;
 
+    void updateFilterReferences(const FilterOperations& filters) final;
+
 private:
     friend class CanvasRenderingContext2DAutoRestoreSkCanvas;
 
     CanvasRenderingContext2D(HTMLCanvasElement*, const CanvasContextCreationAttributes& attrs, Document&);
 
     void dispose();
 
     void dispatchContextLostEvent(Timer<CanvasRenderingContext2D>*);
     void dispatchContextRestoredEvent(Timer<CanvasRenderingContext2D>*);
     void tryRestoreContextEvent(Timer<CanvasRenderingContext2D>*);
@@ skipping 39 matching lines @@
     HashMap<String, Font> m_fontsResolvedUsingCurrentStyle;
     bool m_pruneLocalFontCacheScheduled;
     ListHashSet<String> m_fontLRUList;
 };
 
 DEFINE_TYPE_CASTS(CanvasRenderingContext2D, CanvasRenderingContext, context, context->is2d(), context.is2d());
 
 } // namespace blink
 
 #endif // CanvasRenderingContext2D_h