Implement Model-Driven-Views spec for Dart

pkg/mdv_observe/test/utils.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 testrunner_test;
+library mdv_observe.test.utils;
 
-import 'dart:html';
 import 'package:unittest/unittest.dart';
 
-main() {
-  test("layout", () {
-    var lbl = new LabelElement();
-    lbl.text = 'Hello Dart!';
-    document.body.nodes.add(lbl);
-  });
-}
-
+// TODO(jmesserly): use matchers when this is supported. For now just
+// compare to toStrings.
+expectChanges(actual, expected, {reason}) =>
+    expect('$actual', '$expected', reason: reason);