Use toSVGFontElement() instead of static_cast<SVGFontElement*>

Source/core/svg/SVGFontFaceElement.cpp

 /*
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2008 Apple Inc. 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.
  *
@@ skipping 270 matching lines @@
 
     for (Node* child = firstChild(); child && !srcElement; child = child->nextSibling()) {
         if (child->hasTagName(font_face_srcTag))
             srcElement = static_cast<SVGFontFaceSrcElement*>(child);
     }
 
     bool describesParentFont = parentNode()->hasTagName(SVGNames::fontTag);
     RefPtr<CSSValueList> list;
 
     if (describesParentFont) {
-        m_fontElement = static_cast<SVGFontElement*>(parentNode());
+        m_fontElement = toSVGFontElement(parentNode());
 
         list = CSSValueList::createCommaSeparated();
         list->append(CSSFontFaceSrcValue::createLocal(fontFamily()));
     } else {
         m_fontElement = 0;
         if (srcElement)
             list = srcElement->srcValue();
     }
 
     if (!list || !list->length())
@@ skipping 46 matching lines @@
 
 void SVGFontFaceElement::childrenChanged(bool changedByParser, Node* beforeChange, Node* afterChange, int childCountDelta)
 {
     SVGElement::childrenChanged(changedByParser, beforeChange, afterChange, childCountDelta);
     rebuildFontFace();
 }
 
 } // namespace WebCore
 
 #endif // ENABLE(SVG_FONTS)