Support an Event Path API

Source/core/dom/TreeScope.cpp

 /*
  * Copyright (C) 2011 Google Inc. All Rights Reserved.
  * Copyright (C) 2012 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 423 matching lines @@
 }
 #endif
 
 int TreeScope::refCount() const
 {
     if (Node* root = rootNode())
         return root->refCount();
     return 0;
 }
 
+bool TreeScope::isInclusiveAncestorOf(const TreeScope* scope) const
+{
+    ASSERT(scope);
+    for (; scope; scope = scope->parentTreeScope()) {
+        if (scope == this)
+            return true;
+    }
+    return false;
+}
+
 } // namespace WebCore