Make Document::implementation() method return reference

Source/core/dom/Document.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 656 matching lines @@
     m_docType = docType;
     if (m_docType) {
         this->adoptIfNeeded(*m_docType);
         if (m_docType->publicId().startsWith("-//wapforum//dtd xhtml mobile 1.", /* caseSensitive */ false))
             m_isMobileDocument = true;
     }
     // Doctype affects the interpretation of the stylesheets.
     clearStyleResolver();
 }
 
-DOMImplementation* Document::implementation()
+DOMImplementation& Document::implementation()
 {
     if (!m_implementation)
         m_implementation = DOMImplementation::create(*this);
-    return m_implementation.get();
+    return *m_implementation;
 }
 
 bool Document::hasManifest() const
 {
     return documentElement() && documentElement()->hasTagName(htmlTag) && documentElement()->hasAttribute(manifestAttr);
 }
 
 Location* Document::location() const
 {
     if (!frame())
@@ skipping 449 matching lines @@
     if (m_contentLanguage == language)
         return;
     m_contentLanguage = language;
 
     // Document's style depends on the content language.
     setNeedsStyleRecalc(SubtreeStyleChange);
 }
 
 void Document::setXMLVersion(const String& version, ExceptionState& exceptionState)
 {
-    if (!implementation()->hasFeature("XML", String())) {
+    if (!implementation().hasFeature("XML", String())) {
         exceptionState.throwDOMException(NotSupportedError, "This document does not support XML.");
         return;
     }
 
     if (!XMLDocumentParser::supportsXMLVersion(version)) {
         exceptionState.throwDOMException(NotSupportedError, "This document does not support the XML version '" + version + "'.");
         return;
     }
 
     m_xmlVersion = version;
 }
 
 void Document::setXMLStandalone(bool standalone, ExceptionState& exceptionState)
 {
-    if (!implementation()->hasFeature("XML", String())) {
+    if (!implementation().hasFeature("XML", String())) {
         exceptionState.throwDOMException(NotSupportedError, "This document does not support XML.");
         return;
     }
 
     m_xmlStandalone = standalone ? Standalone : NotStandalone;
 }
 
 KURL Document::baseURI() const
 {
     return m_baseURL;
@@ skipping 4257 matching lines @@
 void Document::defaultEventHandler(Event* event)
 {
     if (frame() && frame()->remotePlatformLayer()) {
         frame()->chromeClient().forwardInputEvent(this, event);
         return;
     }
     Node::defaultEventHandler(event);
 }
 
 } // namespace WebCore