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

Source/core/dom/shadow/ComposedTreeTraversal.h

Index: Source/core/dom/shadow/ComposedTreeTraversal.h
diff --git a/Source/core/dom/shadow/ComposedTreeTraversal.h b/Source/core/dom/shadow/ComposedTreeTraversal.h
index 818047a44d14703355eae93436088a117f807784..07eb955b17af2a9d269e552a7d0c500c7b1ccb2e 100644
--- a/Source/core/dom/shadow/ComposedTreeTraversal.h
+++ b/Source/core/dom/shadow/ComposedTreeTraversal.h
@@ -118,7 +118,7 @@ private:
     static void assertPrecondition(const Node& node)
     {
 #if ENABLE(ASSERT)
-        ASSERT(node.inDocument() ? !node.document().childNeedsDistributionRecalc() : !node.childNeedsDistributionRecalc());
+        ASSERT(!node.needsDistributionRecalc());
         ASSERT(node.canParticipateInComposedTree());
 #endif
     }