Have ElementData::attributeItem() return 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 167 matching lines @@
     String codebase;
     if (MIMETypeRegistry::isJavaAppletMIMEType(serviceType)) {
         codebase = "codebase";
         uniqueParamNames.add(codebase.impl()); // pretend we found it in a PARAM already
     }
 
     // Turn the attributes of the <object> element into arrays, but don't override <param> values.
     if (hasAttributes()) {
         unsigned attributeCount = this->attributeCount();
         for (unsigned i = 0; i < attributeCount; ++i) {
-            const Attribute* attribute = attributeItem(i);
-            const AtomicString& name = attribute->name().localName();
+            const Attribute& attribute = attributeItem(i);
+            const AtomicString& name = attribute.name().localName();
             if (!uniqueParamNames.contains(name.impl())) {
                 paramNames.append(name.string());
-                paramValues.append(attribute->value().string());
+                paramValues.append(attribute.value().string());
             }
         }
     }
 
     mapDataParamToSrc(&paramNames, &paramValues);
 
     // HTML5 says that an object resource's URL is specified by the object's data
     // attribute, not by a param element. However, for compatibility, allow the
     // resource's URL to be given by a param named "src", "movie", "code" or "url"
     // if we know that resource points to a plug-in.
@@ skipping 274 matching lines @@
 {
     return fastHasAttribute(usemapAttr);
 }
 
 bool HTMLObjectElement::useFallbackContent() const
 {
     return HTMLPlugInElement::useFallbackContent() || m_useFallbackContent;
 }
 
 }