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

Source/core/fetch/ImageResourceClient.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 26 matching lines @@
     virtual ResourceClientType resourceClientType() const override final { return expectedType(); }
 
     // Called whenever a frame of an image changes, either because we got more data from the network or
     // because we are animating. If not null, the IntRect is the changed rect of the image.
     virtual void imageChanged(ImageResource*, const IntRect* = 0) { }
 
     // Called to find out if this client wants to actually display the image. Used to tell when we
     // can halt animation. Content nodes that hold image refs for example would not render the image,
     // but RenderImages would (assuming they have visibility: visible and their render tree isn't hidden
     // e.g., in the b/f cache or in a background tab).
-    virtual bool willRenderImage(ImageResource*) { return false; }
+    virtual bool willRenderImage(ImageResource*, bool repeated = false) { return false; }
 };
 
 }
 
 #endif