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

Source/core/svg/SVGSVGElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2006 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2010 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2014 Google, Inc.
  *
  * 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 322 matching lines @@
         && r1.y() < r2.maxY() && r2.y() < r1.maxY();
 }
 
 // One of the element types that can cause graphics to be drawn onto the target canvas.
 // Specifically: circle, ellipse, image, line, path, polygon, polyline, rect, text and use.
 static bool isIntersectionOrEnclosureTarget(RenderObject* renderer)
 {
     return renderer->isSVGShape()
         || renderer->isSVGText()
         || renderer->isSVGImage()
-        || renderer->node()->hasTagName(SVGNames::useTag);
+        || isSVGUseElement(*renderer->node());
 }
 
 bool SVGSVGElement::checkIntersectionOrEnclosure(const SVGElement& element, const FloatRect& rect,
     CheckIntersectionOrEnclosure mode) const
 {
     RenderObject* renderer = element.renderer();
     ASSERT(!renderer || renderer->style());
     if (!renderer || renderer->style()->pointerEvents() == PE_NONE)
         return false;
 
@@ skipping 478 matching lines @@
     Vector<Element*>::const_iterator end = elements.end();
     for (Vector<Element*>::const_iterator it = elements.begin(); it != end; ++it) {
         if ((*it)->isDescendantOf(this))
             return *it;
     }
 
     return 0;
 }
 
 }