fixes to polymer, gets tests back to a stable state

samples/third_party/todomvc/test/markdone_test.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library todomvc.test.markdone_test;
 
 import 'dart:html';
+import 'package:polymer/platform.dart' show endOfMicrotask;
 import 'package:polymer/polymer.dart';
 import 'package:unittest/unittest.dart';
 import 'package:unittest/html_config.dart';
 import '../web/model.dart';
 
 Node findWithText(Node node, String text) {
   if (node.text == text) return node;
   if (node is Element && (node as Element).localName == 'polymer-element') {
     return null;
   }
@@ skipping 32 matching lines @@
   useHtmlConfiguration();
 
   setUp(() => Polymer.onReady);
 
   test('mark done', () {
     appModel.todos.add(new Todo('one (unchecked)'));
     appModel.todos.add(new Todo('two (unchecked)'));
     appModel.todos.add(new Todo('three (checked)')..done = true);
     appModel.todos.add(new Todo('four (checked)'));
 
-    performMicrotaskCheckpoint();
-    var body = query('body');
+    endOfMicrotask(expectAsync0(() {
+      var body = query('body');
 
-    var label = findWithText(body, 'four (checked)');
-    expect(label is LabelElement, isTrue, reason: 'text is in a label: $label');
+      var label = findWithText(body, 'four (checked)');
+      expect(label is LabelElement, isTrue, reason: 'text is in a label: $label');

[Siggi Cherem (dart-lang), 2013/10/21 21:07:42]

80

[Jennifer Messerly, 2013/10/21 21:42:56]

Done.

 
-    var host = findShadowHost(body, label.parentNode);
-    var node = host.parent.query('input');
-    expect(node is InputElement, isTrue, reason: 'node is a checkbox');
-    expect(node.type, 'checkbox', reason: 'node type is checkbox');
-    expect(node.checked, isFalse, reason: 'element is unchecked');
+      var host = findShadowHost(body, label.parentNode);
+      var node = host.parent.query('input');
+      expect(node is InputElement, isTrue, reason: 'node is a checkbox');
+      expect(node.type, 'checkbox', reason: 'node type is checkbox');
+      expect(node.checked, isFalse, reason: 'element is unchecked');
 
-    node.dispatchEvent(new MouseEvent('click', detail: 1));
-    expect(node.checked, isTrue, reason: 'element is checked');
+      node.dispatchEvent(new MouseEvent('click', detail: 1));
+      expect(node.checked, isTrue, reason: 'element is checked');
+    }));
   });
 }