Have StyleResolver / StyleResolverState deal with Document references, not pointers

Source/core/css/resolver/StyleResolverState.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  *
  * 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
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 11 matching lines @@
 #include "config.h"
 #include "core/css/resolver/StyleResolverState.h"
 
 #include "core/dom/Element.h"
 #include "core/dom/Node.h"
 #include "core/dom/NodeRenderStyle.h"
 #include "core/page/Page.h"
 
 namespace WebCore {
 
-StyleResolverState::StyleResolverState(Document* document, Element* element, RenderStyle* parentStyle, RenderRegion* regionForStyling)
-    : m_regionForStyling(0)
+StyleResolverState::StyleResolverState(Document& document, Element* element, RenderStyle* parentStyle, RenderRegion* regionForStyling)
+    : m_elementContext(element ? ElementResolveContext(element) : ElementResolveContext())
+    , m_document(element ? m_elementContext.document() : document)
+    , m_regionForStyling(0)
     , m_applyPropertyToRegularStyle(true)
     , m_applyPropertyToVisitedLinkStyle(false)
     , m_lineHeightValue(0)
     , m_styleMap(*this, m_elementStyleResources)
 {
-    if (element) {
-        m_elementContext = ElementResolveContext(element);
-        m_document = &m_elementContext.document();
-    } else {
-        m_elementContext = ElementResolveContext();
-        m_document = document;
-    }
-
     m_regionForStyling = regionForStyling;
 
     if (m_elementContext.resetStyleInheritance())
         m_parentStyle = 0;
     else if (parentStyle)
         m_parentStyle = parentStyle;
     else if (m_elementContext.parentNode())
         m_parentStyle = m_elementContext.parentNode()->renderStyle();
     else
         m_parentStyle = 0;
 
     m_style = 0;
     m_elementStyleResources.clear();
     m_fontBuilder.clear();
 
     // FIXME: StyleResolverState is never passed between documents
     // so we should be able to do this initialization at StyleResolverState
     // createion time instead of now, correct?
-    if (Page* page = document->page())
+    if (Page* page = document.page())
         m_elementStyleResources.setDeviceScaleFactor(page->deviceScaleFactor());
 }
 
 StyleResolverState::~StyleResolverState()
 {
     m_elementContext = ElementResolveContext();
     m_style = 0;
     m_parentStyle = 0;
     m_regionForStyling = 0;
     m_elementStyleResources.clear();
     m_fontBuilder.clear();
 }
 
 } // namespace WebCore