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

Source/core/html/HTMLOptionElement.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@nypop.com)
  * Copyright (C) 2004, 2005, 2006, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2011 Motorola Mobility, Inc.  All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 92 matching lines @@
 }
 
 bool HTMLOptionElement::rendererIsFocusable() const
 {
     // Option elements do not have a renderer so we check the renderStyle instead.
     return renderStyle() && renderStyle()->display() != NONE;
 }
 
 String HTMLOptionElement::text() const
 {
-    Document* document = this->document();
+    Document& document = this->document();
     String text;
 
     // WinIE does not use the label attribute, so as a quirk, we ignore it.
-    if (!document->inQuirksMode())
+    if (!document.inQuirksMode())
         text = fastGetAttribute(labelAttr);
 
     // FIXME: The following treats an element with the label attribute set to
     // the empty string the same as an element with no label attribute at all.
     // Is that correct? If it is, then should the label function work the same way?
     if (text.isEmpty())
         text = collectOptionInnerText();
 
     // FIXME: Is displayStringModifiedByEncoding helpful here?
     // If it's correct here, then isn't it needed in the value and label functions too?
-    return document->displayStringModifiedByEncoding(text).stripWhiteSpace(isHTMLSpace).simplifyWhiteSpace(isHTMLSpace);
+    return document.displayStringModifiedByEncoding(text).stripWhiteSpace(isHTMLSpace).simplifyWhiteSpace(isHTMLSpace);
 }
 
 void HTMLOptionElement::setText(const String &text, ExceptionState& es)
 {
     RefPtr<Node> protectFromMutationEvents(this);
 
     // Changing the text causes a recalc of a select's items, which will reset the selected
     // index to the first item if the select is single selection with a menu list. We attempt to
     // preserve the selected item.
     RefPtr<HTMLSelectElement> select = ownerSelectElement();
     bool selectIsMenuList = select && select->usesMenuList();
     int oldSelectedIndex = selectIsMenuList ? select->selectedIndex() : -1;
 
     // Handle the common special case where there's exactly 1 child node, and it's a text node.
     Node* child = firstChild();
     if (child && child->isTextNode() && !child->nextSibling())
         toText(child)->setData(text);
     else {
         removeChildren();
-        appendChild(Text::create(document(), text), es);
+        appendChild(Text::create(&document(), text), es);
     }
 
     if (selectIsMenuList && select->selectedIndex() != oldSelectedIndex)
         select->setSelectedIndex(oldSelectedIndex);
 }
 
 void HTMLOptionElement::accessKeyAction(bool)
 {
     HTMLSelectElement* select = ownerSelectElement();
     if (select)
@@ skipping 209 matching lines @@
         // Text nodes inside script elements are not part of the option text.
         if (node->isElementNode() && toScriptLoaderIfPossible(toElement(node)))
             node = NodeTraversal::nextSkippingChildren(node, this);
         else
             node = NodeTraversal::next(node, this);
     }
     return text.toString();
 }
 
 } // namespace WebCore