Always traverse the FUNCTION node in renameNamespaceShadows() of Scop…

…edAliases

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=99189788

src/com/google/javascript/jscomp/ScopedAliases.java

@@ -538,7 +538,13 @@ private void renameNamespaceShadows(NodeTraversal t) {
         }
         MakeDeclaredNamesUnique uniquifier =
             new MakeDeclaredNamesUnique(renamer);
-        NodeTraversal.traverse(compiler, t.getScopeRoot(), uniquifier);
+        Node scopeRoot = t.getScopeRoot();
+        // If in ES6 mode, pass the FUNCTION node as root for traversal to meet
+        // MakeDeclaredNamesUnique's assumption.
+        if (scopeRoot.isBlock() && scopeRoot.getParent().isFunction()) {
+          scopeRoot = scopeRoot.getParent();
+        }
+        NodeTraversal.traverse(compiler, scopeRoot, uniquifier);
       }
     }