Create manager to track OffscreenCanvasSurfaceImpl instances

third_party/WebKit/Source/core/html/HTMLCanvasElement.h

 /*
  * Copyright (C) 2004, 2006, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. 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.
@@ skipping 207 matching lines @@
 
   // For Canvas HitRegions
   bool isSupportedInteractiveCanvasFallback(const Element&);
   HitTestCanvasResult* getControlAndIdIfHitRegionExists(const LayoutPoint&);
   String getIdFromControl(const Element*);
 
   // For OffscreenCanvas that controls this html canvas element
   CanvasSurfaceLayerBridge* surfaceLayerBridge() const {
     return m_surfaceLayerBridge.get();
   }
-  bool createSurfaceLayer();
+  bool createSurfaceLayer(int canvasId);
 
   void detachContext() { m_context = nullptr; }
 
  protected:
   void didMoveToNewDocument(Document& oldDocument) override;
 
  private:
   explicit HTMLCanvasElement(Document&);
   void dispose();
 
@@ skipping 63 matching lines @@
   // Used for OffscreenCanvas that controls this HTML canvas element
   std::unique_ptr<CanvasSurfaceLayerBridge> m_surfaceLayerBridge;
 
   int m_numFramesSinceLastRenderingModeSwitch;
   bool m_pendingRenderingModeSwitch;
 };
 
 }  // namespace blink
 
 #endif  // HTMLCanvasElement_h