Use isSVG*Element() helpers more in SVG code (Part 3)

Source/core/rendering/svg/RenderSVGTSpan.cpp

 /*
  * This file is part of the WebKit project.
  *
  * Copyright (C) 2006 Oliver Hunt <ojh16@student.canterbury.ac.nz>
  * Copyright (C) 2006 Apple Computer 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.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */
 
 #include "config.h"
 
 #include "core/rendering/svg/RenderSVGTSpan.h"
 
 #include "SVGNames.h"
 #include "core/rendering/svg/SVGRenderSupport.h"
+#include "core/svg/SVGAltGlyphElement.h"
 
 namespace WebCore {
 
 RenderSVGTSpan::RenderSVGTSpan(Element* element)
     : RenderSVGInline(element)
 {
 }
 
 bool RenderSVGTSpan::isChildAllowed(RenderObject* child, RenderStyle*) const
 {
     // Always allow text (except empty textnodes and <br>).
     if (child->isText())
         return SVGRenderSupport::isRenderableTextNode(child);
 
 #if ENABLE(SVG_FONTS)
     // Only allow other types of  children if this is not an 'altGlyph'.
-    if (node()->hasTagName(SVGNames::altGlyphTag))
+    ASSERT(node());
+    if (isSVGAltGlyphElement(*node()))
         return false;
 #endif
 
     return child->isSVGInline() && !child->isSVGTextPath();
 }
 
 }