Add toHTMLMetaElement(), and use it.

Source/core/html/HTMLObjectElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Stefan Schimanski (1Stein@gmx.de)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  *
  * 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
@@ skipping 223 matching lines @@
     if (!document().page()
         || !document().page()->settings().needsSiteSpecificQuirks()
         || hasFallbackContent()
         || !equalIgnoringCase(classId(), "clsid:02BF25D5-8C17-4B23-BC80-D3488ABDDC6B"))
         return false;
 
     RefPtr<NodeList> metaElements = document().getElementsByTagName(HTMLNames::metaTag.localName());
     unsigned length = metaElements->length();
     for (unsigned i = 0; i < length; ++i) {
         ASSERT(metaElements->item(i)->isHTMLElement());
-        HTMLMetaElement* metaElement = static_cast<HTMLMetaElement*>(metaElements->item(i));
+        HTMLMetaElement* metaElement = toHTMLMetaElement(metaElements->item(i));
         if (equalIgnoringCase(metaElement->name(), "generator") && metaElement->content().startsWith("Mac OS X Server Web Services Server", false))
             return true;
     }
 
     return false;
 }
 
 bool HTMLObjectElement::hasValidClassId()
 {
     if (MIMETypeRegistry::isJavaAppletMIMEType(serviceType()) && classId().startsWith("java:", false))
@@ skipping 248 matching lines @@
     encoding.appendData(name(), value);
     return true;
 }
 
 HTMLFormElement* HTMLObjectElement::virtualForm() const
 {
     return FormAssociatedElement::form();
 }
 
 }