Have ElementTraversal::firstWithin() take a reference

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 373 matching lines @@
 
     // FIXME: Style gets recalculated which is suboptimal.
     reattachFallbackContent();
 }
 
 bool HTMLObjectElement::containsJavaApplet() const
 {
     if (MIMETypeRegistry::isJavaAppletMIMEType(getAttribute(typeAttr)))
         return true;
 
-    for (Element* child = ElementTraversal::firstWithin(this); child; child = ElementTraversal::nextSkippingChildren(child, this)) {
+    for (Element* child = ElementTraversal::firstWithin(*this); child; child = ElementTraversal::nextSkippingChildren(child, this)) {
         if (child->hasTagName(paramTag)
                 && equalIgnoringCase(child->getNameAttribute(), "type")
                 && MIMETypeRegistry::isJavaAppletMIMEType(child->getAttribute(valueAttr).string()))
             return true;
         if (child->hasTagName(objectTag) && toHTMLObjectElement(child)->containsJavaApplet())
             return true;
         if (child->hasTagName(appletTag))
             return true;
     }
 
@@ skipping 38 matching lines @@
 {
     return FormAssociatedElement::form();
 }
 
 bool HTMLObjectElement::isInteractiveContent() const
 {
     return fastHasAttribute(usemapAttr);
 }
 
 }