Introduce toSVGSMILElement, and use it

Source/core/svg/SVGAElement.cpp

 /*
  * Copyright (C) 2004, 2005, 2008 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2004, 2005, 2007 Rob Buis <buis@kde.org>
  * Copyright (C) 2007 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2010 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 147 matching lines @@
             dispatchSimulatedClick(event);
             return;
         }
 
         if (isLinkClick(event)) {
             String url = stripLeadingAndTrailingHTMLSpaces(hrefCurrentValue());
 
             if (url[0] == '#') {
                 Element* targetElement = treeScope()->getElementById(url.substring(1));
                 if (SVGSMILElement::isSMILElement(targetElement)) {
-                    static_cast<SVGSMILElement*>(targetElement)->beginByLinkActivation();
+                    toSVGSMILElement(targetElement)->beginByLinkActivation();
                     event->setDefaultHandled();
                     return;
                 }
                 // Only allow navigation to internal <view> anchors.
                 if (targetElement && !targetElement->hasTagName(SVGNames::viewTag))
                     return;
             }
 
             String target = this->target();
             if (target.isEmpty() && fastGetAttribute(XLinkNames::showAttr) == "new")
@@ skipping 56 matching lines @@
     // The 'a' element may contain any element that its parent may contain, except itself.
     if (childContext.node()->hasTagName(SVGNames::aTag))
         return false;
     if (parentNode() && parentNode()->isSVGElement())
         return parentNode()->childShouldCreateRenderer(childContext);
 
     return SVGElement::childShouldCreateRenderer(childContext);
 }
 
 } // namespace WebCore