Support the essential part of Shadow DOM v1

third_party/WebKit/Source/core/dom/Element.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Peter Kelly (pmk@post.com)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012, 2013 Apple Inc. All rights reserved.
  *           (C) 2007 Eric Seidel (eric@webkit.org)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1545 matching lines @@
 {
     ASSERT(document().inStyleRecalc());
 
     // We've already been through detach when doing an attach, but we might
     // need to clear any state that's been added since then.
     if (hasRareData() && styleChangeType() == NeedsReattachStyleChange) {
         ElementRareData* data = elementRareData();
         data->clearComputedStyle();
     }
 
-    if (!isActiveInsertionPoint(*this))
+    if (!isSlotOrActiveInsertionPoint())
         LayoutTreeBuilderForElement(*this, context.resolvedStyle).createLayoutObjectIfNeeded();
 
     addCallbackSelectors();
 
     if (hasRareData() && !layoutObject()) {
         if (ElementAnimations* elementAnimations = elementRareData()->elementAnimations()) {
             elementAnimations->cssAnimations().cancel();
             elementAnimations->setAnimationStyleChange(false);
         }
     }
@@ skipping 2067 matching lines @@
 {
 #if ENABLE(OILPAN)
     if (hasRareData())
         visitor->trace(elementRareData());
     visitor->trace(m_elementData);
 #endif
     ContainerNode::trace(visitor);
 }
 
 } // namespace blink