Have Node::document() return a reference instead of a pointer

Source/core/dom/TreeScope.cpp

 /*
  * Copyright (C) 2011 Google Inc. All Rights Reserved.
  * Copyright (C) 2012 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 191 matching lines @@
 }
 
 HTMLMapElement* TreeScope::getImageMap(const String& url) const
 {
     if (url.isNull())
         return 0;
     if (!m_imageMapsByName)
         return 0;
     size_t hashPos = url.find('#');
     String name = (hashPos == notFound ? url : url.substring(hashPos + 1)).impl();
-    if (rootNode()->document()->isHTMLDocument())
+    if (rootNode()->document().isHTMLDocument())
         return toHTMLMapElement(m_imageMapsByName->getElementByLowercasedMapName(AtomicString(name.lower()).impl(), this));
     return toHTMLMapElement(m_imageMapsByName->getElementByMapName(AtomicString(name).impl(), this));
 }
 
 Node* nodeFromPoint(Document* document, int x, int y, LayoutPoint* localPoint)
 {
     Frame* frame = document->frame();
 
     if (!frame)
         return 0;
@@ skipping 12 matching lines @@
     document->renderView()->hitTest(request, result);
 
     if (localPoint)
         *localPoint = result.localPoint();
 
     return result.innerNode();
 }
 
 Element* TreeScope::elementFromPoint(int x, int y) const
 {
-    Node* node = nodeFromPoint(rootNode()->document(), x, y);
+    Node* node = nodeFromPoint(&rootNode()->document(), x, y);
     if (node && node->isTextNode())
         node = node->parentNode();
     ASSERT(!node || node->isElementNode() || node->isShadowRoot());
     node = ancestorInThisScope(node);
     if (!node || !node->isElementNode())
         return 0;
     return toElement(node);
 }
 
 void TreeScope::addLabel(const AtomicString& forAttributeValue, HTMLLabelElement* element)
@@ skipping 24 matching lines @@
                     addLabel(forValue, label);
             }
         }
     }
 
     return toHTMLLabelElement(m_labelsByForAttribute->getElementByLabelForAttribute(forAttributeValue.impl(), this));
 }
 
 DOMSelection* TreeScope::getSelection() const
 {
-    if (!rootNode()->document()->frame())
+    if (!rootNode()->document().frame())
         return 0;
 
     if (m_selection)
         return m_selection.get();
 
     // FIXME: The correct selection in Shadow DOM requires that Position can have a ShadowRoot
     // as a container.
     // See https://bugs.webkit.org/show_bug.cgi?id=82697
     m_selection = DOMSelection::create(this);
     return m_selection.get();
 }
 
 Element* TreeScope::findAnchor(const String& name)
 {
     if (name.isEmpty())
         return 0;
     if (Element* element = getElementById(name))
         return element;
     for (Element* element = ElementTraversal::firstWithin(rootNode()); element; element = ElementTraversal::next(element)) {
         if (isHTMLAnchorElement(element)) {
             HTMLAnchorElement* anchor = toHTMLAnchorElement(element);
-            if (rootNode()->document()->inQuirksMode()) {
+            if (rootNode()->document().inQuirksMode()) {
                 // Quirks mode, case insensitive comparison of names.
                 if (equalIgnoringCase(anchor->name(), name))
                     return anchor;
             } else {
                 // Strict mode, names need to match exactly.
                 if (anchor->name() == name)
                     return anchor;
             }
         }
     }
@@ skipping 20 matching lines @@
 {
     for (; focusedFrame; focusedFrame = focusedFrame->tree()->parent()) {
         if (focusedFrame->tree()->parent() == currentFrame)
             return focusedFrame->ownerElement();
     }
     return 0;
 }
 
 Element* TreeScope::adjustedFocusedElement()
 {
-    Document* document = rootNode()->document();
-    Element* element = document->focusedElement();
-    if (!element && document->page())
-        element = focusedFrameOwnerElement(document->page()->focusController().focusedFrame(), document->frame());
+    Document& document = rootNode()->document();
+    Element* element = document.focusedElement();
+    if (!element && document.page())
+        element = focusedFrameOwnerElement(document.page()->focusController().focusedFrame(), document.frame());
     if (!element)
         return 0;
     Vector<Node*> targetStack;
     for (EventPathWalker walker(element); walker.node(); walker.moveToParent()) {
         Node* node = walker.node();
         if (targetStack.isEmpty())
             targetStack.append(node);
         else if (walker.isVisitingInsertionPointInReprojection())
             targetStack.append(targetStack.last());
         if (node == rootNode()) {
@@ skipping 131 matching lines @@
             result = element;
         for (ShadowRoot* shadowRoot = element->youngestShadowRoot(); shadowRoot; shadowRoot = shadowRoot->olderShadowRoot()) {
             if (Element* shadowResult = shadowRoot->getElementByAccessKey(key))
                 result = shadowResult;
         }
     }
     return result;
 }
 
 } // namespace WebCore