Get rid of TreeBoundaryCrossingRules.

Source/core/dom/shadow/ShadowRoot.h

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Neither the name of Google Inc. nor the names of its
@@ skipping 63 matching lines @@
 
     ShadowRoot* youngerShadowRoot() const { return prev(); }
 
     ShadowRoot* olderShadowRootForBindings() const;
     bool shouldExposeToBindings() const { return type() == OpenShadowRoot; }
 
     bool isYoungest() const { return !youngerShadowRoot(); }
     bool isOldest() const { return !olderShadowRoot(); }
 
     virtual void attach(const AttachContext& = AttachContext()) override;
+    virtual void detach(const AttachContext& = AttachContext()) override;
 
     virtual InsertionNotificationRequest insertedInto(ContainerNode*) override;
     virtual void removedFrom(ContainerNode*) override;
 
     void registerScopedHTMLStyleChild();
     void unregisterScopedHTMLStyleChild();
 
     bool containsShadowElements() const;
     bool containsContentElements() const;
     bool containsInsertionPoints() const { return containsShadowElements() || containsContentElements(); }
@@ skipping 69 matching lines @@
     return adjustedFocusedElement();
 }
 
 DEFINE_NODE_TYPE_CASTS(ShadowRoot, isShadowRoot());
 DEFINE_TYPE_CASTS(ShadowRoot, TreeScope, treeScope, treeScope->rootNode().isShadowRoot(), treeScope.rootNode().isShadowRoot());
 DEFINE_TYPE_CASTS(TreeScope, ShadowRoot, shadowRoot, true, true);
 
 } // namespace blink
 
 #endif // ShadowRoot_h