Introduce few const getters for dom classes

third_party/WebKit/Source/core/css/CSSStyleSheet.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2006, 2007, 2012 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 353 matching lines @@
 
 CSSRuleList* CSSStyleSheet::cssRules()
 {
     if (!canAccessRules())
         return nullptr;
     if (!m_ruleListCSSOMWrapper)
         m_ruleListCSSOMWrapper = StyleSheetCSSRuleList::create(this);
     return m_ruleListCSSOMWrapper.get();
 }
 
+CSSRuleList* CSSStyleSheet::maybeCssRules() const
+{
+    return m_ruleListCSSOMWrapper.get();
+}
+
 String CSSStyleSheet::href() const
 {
     return m_contents->originalURL();
 }
 
 KURL CSSStyleSheet::baseURL() const
 {
     return m_contents->baseURL();
 }
 
@@ skipping 71 matching lines @@
     visitor->trace(m_mediaQueries);
     visitor->trace(m_ownerNode);
     visitor->trace(m_ownerRule);
     visitor->trace(m_mediaCSSOMWrapper);
     visitor->trace(m_childRuleCSSOMWrappers);
     visitor->trace(m_ruleListCSSOMWrapper);
     StyleSheet::trace(visitor);
 }
 
 } // namespace blink