Should remove ScopedStyleResolver when ShadowRoot is removed from docoument.

Source/core/css/resolver/StyleResolver.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 2004-2005 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2006, 2007 Nicholas Shanks (webkit@nickshanks.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alexey Proskuryakov <ap@webkit.org>
  * Copyright (C) 2007, 2008 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
@@ skipping 221 matching lines @@
     m_features.clear();
     m_siblingRuleSet.clear();
     m_uncommonAttributeRuleSet.clear();
     m_needCollectFeatures = true;
 }
 
 void StyleResolver::processScopedRules(const RuleSet& authorRules, CSSStyleSheet* parentStyleSheet, unsigned parentIndex, ContainerNode& scope)
 {
     const WillBeHeapVector<RawPtrWillBeMember<StyleRuleKeyframes> > keyframesRules = authorRules.keyframesRules();
     ScopedStyleResolver* resolver = &scope.treeScope().ensureScopedStyleResolver();
-    document().styleEngine()->addScopedStyleResolver(resolver);
     for (unsigned i = 0; i < keyframesRules.size(); ++i)
         resolver->addKeyframeStyle(keyframesRules[i]);
 
     m_treeBoundaryCrossingRules.addTreeBoundaryCrossingRules(authorRules, parentStyleSheet, parentIndex, scope);
 
     // FIXME(BUG 72461): We don't add @font-face rules of scoped style sheets for the moment.
     if (scope.isDocumentNode()) {
         const WillBeHeapVector<RawPtrWillBeMember<StyleRuleFontFace> > fontFaceRules = authorRules.fontFaceRules();
         for (unsigned i = 0; i < fontFaceRules.size(); ++i)
             addFontFaceRule(m_document, document().styleEngine()->fontSelector(), fontFaceRules[i]);
@@ skipping 1339 matching lines @@
     visitor->trace(m_uncommonAttributeRuleSet);
     visitor->trace(m_watchedSelectorsRules);
     visitor->trace(m_treeBoundaryCrossingRules);
     visitor->trace(m_styleSharingLists);
     visitor->trace(m_pendingStyleSheets);
     visitor->trace(m_document);
 #endif
 }
 
 } // namespace blink