Remove isSupportedAttribute in svg

Source/core/svg/SVGFEDropShadowElement.h

 /*
  * Copyright (C) Research In Motion Limited 2011. 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 28 matching lines @@
     SVGAnimatedNumber* dy() { return m_dy.get(); }
     SVGAnimatedNumber* stdDeviationX() { return m_stdDeviation->firstNumber(); }
     SVGAnimatedNumber* stdDeviationY() { return m_stdDeviation->secondNumber(); }
     SVGAnimatedString* in1() { return m_in1.get(); }
 
     DECLARE_VIRTUAL_TRACE();
 
 private:
     explicit SVGFEDropShadowElement(Document&);
 
-    bool isSupportedAttribute(const QualifiedName&);
     virtual void svgAttributeChanged(const QualifiedName&) override;
     virtual PassRefPtrWillBeRawPtr<FilterEffect> build(SVGFilterBuilder*, Filter*) override;
 
     static const AtomicString& stdDeviationXIdentifier();
     static const AtomicString& stdDeviationYIdentifier();
 
     RefPtrWillBeMember<SVGAnimatedNumber> m_dx;
     RefPtrWillBeMember<SVGAnimatedNumber> m_dy;
     RefPtrWillBeMember<SVGAnimatedNumberOptionalNumber> m_stdDeviation;
     RefPtrWillBeMember<SVGAnimatedString> m_in1;
 };
 
 } // namespace blink
 
 #endif // SVGFEDropShadowElement_h