Expose setting API to set ImageAnimationPolicy(Allowed, Once, None)

Source/core/fetch/ImageResource.h

 /*
     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2001 Dirk Mueller <mueller@kde.org>
     Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
     Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
     License as published by the Free Software Foundation; either
     version 2 of the License, or (at your option) any later version.
@@ skipping 92 matching lines @@
 
     virtual bool isImage() const override { return true; }
     virtual bool stillNeedsLoad() const override { return !errorOccurred() && status() == Unknown && !isLoading(); }
 
     // ImageObserver
     virtual void decodedSizeChanged(const blink::Image*, int delta) override;
     virtual void didDraw(const blink::Image*) override;
 
     virtual bool shouldPauseAnimation(const blink::Image*) override;
     virtual void animationAdvanced(const blink::Image*) override;
+    virtual void imageAnimationPolicy(const blink::Image*, ImageAnimationPolicy&) override;
     virtual void changedInRect(const blink::Image*, const IntRect&) override;
 
 protected:
     virtual bool isSafeToUnlock() const override;
     virtual void destroyDecodedDataIfPossible() override;
 
 private:
     void clear();
 
     void setCustomAcceptHeader();
@@ skipping 14 matching lines @@
     OwnPtr<SVGImageCache> m_svgImageCache;
     bool m_loadingMultipartContent;
     bool m_hasDevicePixelRatioHeaderValue;
 };
 
 DEFINE_RESOURCE_TYPE_CASTS(Image);
 
 }
 
 #endif