Fixing bots after Polymer element integration

samples/third_party/todomvc/test/mainpage_test.dart

Index: samples/third_party/todomvc/test/mainpage_test.dart
diff --git a/samples/third_party/todomvc/test/mainpage_test.dart b/samples/third_party/todomvc/test/mainpage_test.dart
index dc23b7ef8d03621e180690c0e1e0a8e387147255..8b9a8dc58f972f8a752c7be60e66830d9fcfe874 100644
--- a/samples/third_party/todomvc/test/mainpage_test.dart
+++ b/samples/third_party/todomvc/test/mainpage_test.dart
@@ -4,6 +4,7 @@
 
 library todomvc.test.mainpage_test;
 
+import 'dart:async';
 import 'dart:html';
 import 'package:unittest/unittest.dart';
 import 'package:unittest/html_config.dart';
@@ -17,6 +18,8 @@ import '../web/model.dart';
 main() {
   useHtmlConfiguration();
 
+  setUp(() => new Future.delayed(Duration.ZERO));
+
   test('initial state', () {
     final todoApp = query('todo-app');
     expect(appModel.todos.length, 0);