Avoid parsing css text if there are identical inline style blocks.

Source/core/html/HTMLLinkElement.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Rob Buis (rwlbuis@gmail.com)
  * Copyright (C) 2011 Google 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
@@ skipping 415 matching lines @@
     if (m_sheet)
         clearSheet();
     m_sheet = CSSStyleSheet::create(styleSheet, m_owner);
     m_sheet->setMediaQueries(MediaQuerySet::create(m_owner->media()));
     m_sheet->setTitle(m_owner->title());
 
     styleSheet->parseAuthorStyleSheet(cachedStyleSheet, m_owner->document().securityOrigin());
 
     m_loading = false;
     styleSheet->notifyLoadedSheet(cachedStyleSheet);
-    styleSheet->checkLoaded();
+    styleSheet->checkLoadedFor(m_owner);
 
     if (styleSheet->isCacheable())
         const_cast<CSSStyleSheetResource*>(cachedStyleSheet)->saveParsedStyleSheet(styleSheet);
 }
 
 bool LinkStyle::sheetLoaded()
 {
     if (!styleSheetIsLoading()) {
         removePendingSheet();
         return true;
@@ skipping 185 matching lines @@
 void LinkStyle::ownerRemoved()
 {
     if (m_sheet)
         clearSheet();
 
     if (styleSheetIsLoading())
         removePendingSheet(RemovePendingSheetNotifyLater);
 }
 
 } // namespace WebCore