Collect active stylesheets and and apply asynchronously.

third_party/WebKit/Source/core/dom/ShadowTreeStyleSheetCollection.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)
@@ skipping 18 matching lines @@
 
 #ifndef ShadowTreeStyleSheetCollection_h
 #define ShadowTreeStyleSheetCollection_h
 
 #include "core/dom/TreeScopeStyleSheetCollection.h"
 
 namespace blink {
 
 class ShadowRoot;
 class StyleSheetCollection;
-class StyleEngine;
 
 class ShadowTreeStyleSheetCollection final
     : public TreeScopeStyleSheetCollection {
   WTF_MAKE_NONCOPYABLE(ShadowTreeStyleSheetCollection);
 
  public:
   explicit ShadowTreeStyleSheetCollection(ShadowRoot&);
-
-  void updateActiveStyleSheets(StyleEngine&, StyleResolverUpdateMode);
-
+  void updateActiveStyleSheets();
   bool isShadowTreeStyleSheetCollection() const final { return true; }
 
   DEFINE_INLINE_VIRTUAL_TRACE() {
     TreeScopeStyleSheetCollection::trace(visitor);
   }
 
  private:
-  void collectStyleSheets(StyleEngine&, StyleSheetCollection&);
+  void collectStyleSheets(StyleSheetCollection&);
 };
 
 DEFINE_TYPE_CASTS(ShadowTreeStyleSheetCollection,
                   TreeScopeStyleSheetCollection,
                   value,
                   value->isShadowTreeStyleSheetCollection(),
                   value.isShadowTreeStyleSheetCollection());
 
 }  // namespace blink
 
 #endif