Integrate internal changes
diff --git a/js/debug_test.js b/js/debug_test.js
index 01cbf89..702cc76 100644
--- a/js/debug_test.js
+++ b/js/debug_test.js
@@ -65,7 +65,7 @@
       'aBoolean': true
     }, jspb.debug.dump(message));
 
-    message.setAString(undefined);
+    message.clearAString();
 
     assertObjectEquals({
       $name: 'proto.jspb.test.Simple1',