Make OffscreenCanvas animation in sync with its placeholder canvas's parent frame rate

third_party/WebKit/Source/web/ChromeClientImpl.h

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  *
  * 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.
@@ skipping 203 matching lines @@
 
   std::unique_ptr<WebFrameScheduler> createFrameScheduler(
       BlameContext*) override;
 
   double lastFrameTimeMonotonic() const override;
 
   void notifyPopupOpeningObservers() const;
 
   void installSupplements(LocalFrame&) override;
 
+  WebLayerTreeView* getWebLayerTreeView() override;
+
  private:
   explicit ChromeClientImpl(WebViewImpl*);
 
   bool isChromeClientImpl() const override { return true; }
   void registerPopupOpeningObserver(PopupOpeningObserver*) override;
   void unregisterPopupOpeningObserver(PopupOpeningObserver*) override;
 
   void setCursor(const WebCursorInfo&, LocalFrame*);
 
   WebViewImpl* m_webView;  // Weak pointer.
   WindowFeatures m_windowFeatures;
   Vector<PopupOpeningObserver*> m_popupOpeningObservers;
   Cursor m_lastSetMouseCursorForTesting;
   bool m_cursorOverridden;
   bool m_didRequestNonEmptyToolTip;
 };
 
 DEFINE_TYPE_CASTS(ChromeClientImpl,
                   ChromeClient,
                   client,
                   client->isChromeClientImpl(),
                   client.isChromeClientImpl());
 
 }  // namespace blink
 
 #endif