CSS: Checked downcast for ShadowTreeStyleSheetCollection

third_party/WebKit/Source/core/dom/TreeScopeStyleSheetCollection.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
@@ skipping 34 matching lines @@
 class StyleRuleFontFace;
 
 class CORE_EXPORT TreeScopeStyleSheetCollection : public StyleSheetCollection {
 public:
     void addStyleSheetCandidateNode(Node*);
     void removeStyleSheetCandidateNode(Node* node) { m_styleSheetCandidateNodes.remove(node); }
     bool hasStyleSheetCandidateNodes() const { return !m_styleSheetCandidateNodes.isEmpty(); }
 
     void clearMediaQueryRuleSetStyleSheets();
 
+    virtual bool isShadowTreeStyleSheetCollection() const { return false; }
+
     DECLARE_VIRTUAL_TRACE();
 
 protected:
     explicit TreeScopeStyleSheetCollection(TreeScope&);
 
     Document& document() const { return treeScope().document(); }
     TreeScope& treeScope() const { return *m_treeScope; }
 
     enum StyleResolverUpdateType {
         Reconstruct,
@@ skipping 24 matching lines @@
 protected:
     Member<TreeScope> m_treeScope;
     bool m_hadActiveLoadingStylesheet;
 
     DocumentOrderedList m_styleSheetCandidateNodes;
 };
 
 } // namespace blink
 
 #endif