Remove isSupportedAttribute in svg

Source/core/svg/SVGPathElement.h

 /*
  * Copyright (C) 2004, 2005, 2006, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007 Rob Buis <buis@kde.org>
  *
  * 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.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 83 matching lines @@
 
     void pathSegListChanged(ListModification = ListModificationUnknown);
 
     virtual FloatRect getBBox() override;
 
     DECLARE_VIRTUAL_TRACE();
 
 private:
     explicit SVGPathElement(Document&);
 
-    bool isSupportedAttribute(const QualifiedName&);
     virtual void svgAttributeChanged(const QualifiedName&) override;
 
     virtual Node::InsertionNotificationRequest insertedInto(ContainerNode*) override;
     virtual void removedFrom(ContainerNode*) override;
 
     void invalidateMPathDependencies();
 
     RefPtrWillBeMember<SVGAnimatedNumber> m_pathLength;
     RefPtrWillBeMember<SVGAnimatedPath> m_pathSegList;
 };
 
 } // namespace blink
 
 #endif // SVGPathElement_h