Have LifecycleContext::lifecycleNotifier() return a 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 603 matching lines @@
 
     // FIXME: consider using ActiveDOMObject.
     if (m_scriptedAnimationController)
         m_scriptedAnimationController->clearDocumentPointer();
     m_scriptedAnimationController.clear();
 
     if (svgExtensions())
         accessSVGExtensions()->pauseAnimations();
 
     m_lifecyle.advanceTo(DocumentLifecycle::Disposed);
-    lifecycleNotifier()->notifyDocumentWasDisposed();
+    lifecycleNotifier().notifyDocumentWasDisposed();
 }
 
 SelectorQueryCache& Document::selectorQueryCache()
 {
     if (!m_selectorQueryCache)
         m_selectorQueryCache = adoptPtr(new SelectorQueryCache());
     return *m_selectorQueryCache;
 }
 
 MediaQueryMatcher& Document::mediaQueryMatcher()
@@ skipping 1407 matching lines @@
     // This is required, as our Frame might delete itself as soon as it detaches
     // us. However, this violates Node::detach() semantics, as it's never
     // possible to re-attach. Eventually Document::detach() should be renamed,
     // or this setting of the frame to 0 could be made explicit in each of the
     // callers of Document::detach().
     m_frame = 0;
 
     if (m_mediaQueryMatcher)
         m_mediaQueryMatcher->documentDestroyed();
 
-    lifecycleNotifier()->notifyDocumentWasDetached();
+    lifecycleNotifier().notifyDocumentWasDetached();
     m_lifecyle.advanceTo(DocumentLifecycle::Stopped);
 }
 
 void Document::prepareForDestruction()
 {
     disconnectDescendantFrames();
 
     // The process of disconnecting descendant frames could have already
     // detached us.
     if (!confusingAndOftenMisusedAttached())
@@ skipping 3262 matching lines @@
 float Document::devicePixelRatio() const
 {
     return m_frame ? m_frame->devicePixelRatio() : 1.0;
 }
 
 PassOwnPtr<LifecycleNotifier<ExecutionContext> > Document::createLifecycleNotifier()
 {
     return DocumentLifecycleNotifier::create(this);
 }
 
-DocumentLifecycleNotifier* Document::lifecycleNotifier()
+DocumentLifecycleNotifier& Document::lifecycleNotifier()
 {
-    return static_cast<DocumentLifecycleNotifier*>(ExecutionContext::lifecycleNotifier());
+    return static_cast<DocumentLifecycleNotifier&>(ExecutionContext::lifecycleNotifier());
 }
 
 void Document::removedStyleSheet(StyleSheet* sheet, RecalcStyleTime when, StyleResolverUpdateMode updateMode)
 {
     if (!isActive())
         return;
 
     styleEngine()->modifiedStyleSheet(sheet);
     styleResolverChanged(when, updateMode);
 }
 
 void Document::modifiedStyleSheet(StyleSheet* sheet, RecalcStyleTime when, StyleResolverUpdateMode updateMode)
 {
     if (!isActive())
         return;
 
     styleEngine()->modifiedStyleSheet(sheet);
     styleResolverChanged(when, updateMode);
 }
 
 } // namespace WebCore