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

Source/core/editing/EditingStyle.cpp

 /*
  * Copyright (C) 2007, 2008, 2009 Apple Computer, Inc.
  * Copyright (C) 2010, 2011 Google 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 1115 matching lines @@
         }
 
         if (mode == OverrideValues || (mode == DoNotOverrideValues && !value))
             m_mutableStyle->setProperty(property.id(), property.value()->cssText(), property.isImportant());
     }
 }
 
 static PassRefPtr<MutableStylePropertySet> styleFromMatchedRulesForElement(Element* element, unsigned rulesToInclude)
 {
     RefPtr<MutableStylePropertySet> style = MutableStylePropertySet::create();
-    RefPtr<CSSRuleList> matchedRules = element->document()->styleResolver()->styleRulesForElement(element, rulesToInclude);
+    RefPtr<CSSRuleList> matchedRules = element->document().styleResolver()->styleRulesForElement(element, rulesToInclude);
     if (matchedRules) {
         for (unsigned i = 0; i < matchedRules->length(); i++) {
             if (matchedRules->item(i)->type() == CSSRule::STYLE_RULE)
                 style->mergeAndOverrideOnConflict(static_cast<CSSStyleRule*>(matchedRules->item(i))->styleRule()->properties());
         }
     }
 
     return style.release();
 }
 
@@ skipping 116 matching lines @@
     // We only do this for range because caret at Position("hello", 5) in <b>hello</b>world should give you font-weight: bold.
     Node* positionNode = position.containerNode();
     if (selection.isRange() && positionNode && positionNode->isTextNode() && position.computeOffsetInContainerNode() == positionNode->maxCharacterOffset())
         position = nextVisuallyDistinctCandidate(position);
 
     Element* element = position.element();
     if (!element)
         return 0;
 
     RefPtr<EditingStyle> style = EditingStyle::create(element, EditingStyle::AllProperties);
-    style->mergeTypingStyle(element->document());
+    style->mergeTypingStyle(&element->document());
 
     // If background color is transparent, traverse parent nodes until we hit a different value or document root
     // Also, if the selection is a range, ignore the background color at the start of selection,
     // and find the background color of the common ancestor.
     if (shouldUseBackgroundColorInEffect && (selection.isRange() || hasTransparentBackgroundColor(style->m_mutableStyle.get()))) {
         RefPtr<Range> range(selection.toNormalizedRange());
         if (PassRefPtr<CSSValue> value = backgroundColorInEffect(range->commonAncestorContainer(IGNORE_EXCEPTION)))
             style->setProperty(CSSPropertyBackgroundColor, value->cssText());
     }
 
@@ skipping 103 matching lines @@
 }
 
 StyleChange::StyleChange(EditingStyle* style, const Position& position)
     : m_applyBold(false)
     , m_applyItalic(false)
     , m_applyUnderline(false)
     , m_applyLineThrough(false)
     , m_applySubscript(false)
     , m_applySuperscript(false)
 {
-    Document* document = position.anchorNode() ? position.anchorNode()->document() : 0;
+    Document* document = position.anchorNode() ? &position.anchorNode()->document() : 0;
     if (!style || !style->style() || !document || !document->frame())
         return;
 
     RefPtr<CSSComputedStyleDeclaration> computedStyle = position.computedStyle();
     // FIXME: take care of background-color in effect
     RefPtr<MutableStylePropertySet> mutableStyle = getPropertiesNotIn(style->style(), computedStyle.get());
 
     reconcileTextDecorationProperties(mutableStyle.get());
     if (!document->frame()->editor().shouldStyleWithCSS())
         extractTextStyles(document, mutableStyle.get(), computedStyle->useFixedFontDefaultSize());
@@ skipping 244 matching lines @@
 {
     for (Node* ancestor = node; ancestor; ancestor = ancestor->parentNode()) {
         RefPtr<CSSComputedStyleDeclaration> ancestorStyle = CSSComputedStyleDeclaration::create(ancestor);
         if (!hasTransparentBackgroundColor(ancestorStyle.get()))
             return ancestorStyle->getPropertyCSSValue(CSSPropertyBackgroundColor);
     }
     return 0;
 }
 
 }