Use isSVG*Element() helpers more in SVG code (Part 4)

Source/core/svg/SVGFEImageElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005 Rob Buis <buis@kde.org>
  * Copyright (C) 2010 Dirk Schulze <krit@webkit.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.
  *
@@ skipping 159 matching lines @@
 }
 
 void SVGFEImageElement::notifyFinished(Resource*)
 {
     if (!inDocument())
         return;
 
     Element* parent = parentElement();
     ASSERT(parent);
 
-    if (!parent->hasTagName(SVGNames::filterTag) || !parent->renderer())
+    if (!isSVGFilterElement(*parent) || !parent->renderer())
         return;
 
     if (RenderObject* renderer = this->renderer())
         RenderSVGResource::markForLayoutAndParentResourceInvalidation(renderer);
 }
 
 PassRefPtr<FilterEffect> SVGFEImageElement::build(SVGFilterBuilder*, Filter* filter)
 {
     if (m_cachedImage)
         return FEImage::createWithImage(filter, m_cachedImage->imageForRenderer(renderer()), m_preserveAspectRatio->currentValue());
     return FEImage::createWithIRIReference(filter, document(), hrefString(), m_preserveAspectRatio->currentValue());
 }
 
 }