Remove dead methods from CSSStyleSheet and StyleSheetContents.

sky/engine/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 59 matching lines @@
 }
 
 void CSSStyleSheet::setMediaQueries(PassRefPtr<MediaQuerySet> mediaQueries)
 {
     m_mediaQueries = mediaQueries;
 
     // Add warning message to inspector whenever dpi/dpcm values are used for "screen" media.
     reportMediaQueryWarningIfNeeded(ownerDocument(), m_mediaQueries.get());
 }
 
-unsigned CSSStyleSheet::length() const
-{
-    return m_contents->ruleCount();
-}
-
 void CSSStyleSheet::clearOwnerNode()
 {
     if (Document* owner = ownerDocument())
         owner->modifiedStyleSheet(this);
     if (m_ownerNode)
         m_contents->unregisterClient(this);
     m_ownerNode = nullptr;
 }
 
 Document* CSSStyleSheet::ownerDocument() const
 {
     return ownerNode() ? &ownerNode()->document() : 0;
 }
 
 } // namespace blink