Make second argument to CSSStyleSheet.insertRule() optional again

Source/core/css/CSSStyleSheet.h

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2006, 2007, 2008, 2009, 2010, 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 46 matching lines @@
     virtual CSSStyleSheet* parentStyleSheet() const OVERRIDE;
     virtual Node* ownerNode() const OVERRIDE { return m_ownerNode; }
     virtual MediaList* media() const OVERRIDE;
     virtual String href() const OVERRIDE;
     virtual String title() const OVERRIDE { return m_title; }
     virtual bool disabled() const OVERRIDE { return m_isDisabled; }
     virtual void setDisabled(bool) OVERRIDE;
 
     PassRefPtr<CSSRuleList> cssRules();
     unsigned insertRule(const String& rule, unsigned index, ExceptionState&);
+    unsigned insertRule(const String& rule, ExceptionState&); // Deprecated.
     void deleteRule(unsigned index, ExceptionState&);
 
     // IE Extensions
     PassRefPtr<CSSRuleList> rules();
     int addRule(const String& selector, const String& style, int index, ExceptionState&);
     int addRule(const String& selector, const String& style, ExceptionState&);
     void removeRule(unsigned index, ExceptionState& exceptionState) { deleteRule(index, exceptionState); }
 
     // For CSSRuleList.
     unsigned length() const;
@@ skipping 83 matching lines @@
 {
     if (m_styleSheet)
         m_styleSheet->didMutateRules();
 }
 
 DEFINE_TYPE_CASTS(CSSStyleSheet, StyleSheet, sheet, sheet->isCSSStyleSheet(), sheet.isCSSStyleSheet());
 
 } // namespace
 
 #endif