Elements moved from a shadow root to a detached tree should clear their IsInShadowTree Flag

Source/core/dom/ContainerNode.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) 2004, 2005, 2006, 2007, 2008, 2009, 2013 Apple 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
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 832 matching lines @@
     }
 }
 
 void ContainerNode::notifyNodeRemoved(Node& root)
 {
     ScriptForbiddenScope forbidScript;
     EventDispatchForbiddenScope assertNoEventDispatch;
 
     for (Node& node : NodeTraversal::inclusiveDescendantsOf(root)) {
         // As an optimization we skip notifying Text nodes and other leaf nodes
-        // of removal when they're not in the Document tree since the virtual
+        // of removal when they're not in the Document tree and not in a shadow root since the virtual
         // call to removedFrom is not needed.
-        if (!node.inDocument() && !node.isContainerNode())
+        if (!node.inDocument() && !node.isContainerNode() && !node.isInShadowTree())

[rhogan, 2015/06/24 20:20:22]

Strictly, shouldn't this be: if (inDocument() ..  rather than if
(!node.inDocument().. , given the assertion is on |this| in removedFrom? I
realize if node is inDocument then |this| probably is too, but stranger things
have happened I guess?

             continue;
         node.removedFrom(this);
         for (ShadowRoot* shadowRoot = node.youngestShadowRoot(); shadowRoot; shadowRoot = shadowRoot->olderShadowRoot())
             notifyNodeRemoved(*shadowRoot);
     }
 }
 
 void ContainerNode::attach(const AttachContext& context)
 {
     attachChildren(context);
@@ skipping 656 matching lines @@
         return true;
 
     if (node->isElementNode() && toElement(node)->shadow())
         return true;
 
     return false;
 }
 #endif
 
 } // namespace blink