Make ComposedTreeTraversal assert a node with Node::needsDistributionRecalc().

Source/core/dom/shadow/ComposedTreeTraversal.h

 /*
  * Copyright (C) 2012 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 100 matching lines @@
 
 private:
     enum TraversalDirection {
         TraversalDirectionForward,
         TraversalDirectionBackward
     };
 
     static void assertPrecondition(const Node& node)
     {
 #if ENABLE(ASSERT)
-        ASSERT(node.inDocument() ? !node.document().childNeedsDistributionRecalc() : !node.childNeedsDistributionRecalc());
+        ASSERT(!node.needsDistributionRecalc());
         ASSERT(node.canParticipateInComposedTree());
 #endif
     }
 
     static void assertPostcondition(const Node* node)
     {
 #if ENABLE(ASSERT)
         if (node)
             assertPrecondition(*node);
 #endif
@@ skipping 167 matching lines @@
 }
 
 inline Node* ComposedTreeTraversal::traverseLastChild(const Node& node)
 {
     return traverseChild(node, TraversalDirectionBackward);
 }
 
 } // namespace
 
 #endif