pkg: analysis aided cleanup

pkg/mdv/test/mdv_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 observe_utils;
 
-import 'dart:async';
 import 'dart:html';
 import 'package:observe/observe.dart';
 import 'package:unittest/unittest.dart';
 
 import 'package:observe/src/microtask.dart';
 export 'package:observe/src/microtask.dart';
 
 final bool parserHasNativeTemplate = () {
   var div = new DivElement()..innerHtml = '<table><template>';
   return div.firstChild.firstChild != null &&
@@ skipping 42 matching lines @@
 
   get bar => _bar;
   set bar(value) {
     _bar = notifyPropertyChange(const Symbol('bar'), _bar, value);
   }
 }
 
 observeTest(name, testCase) => test(name, wrapMicrotask(testCase));
 
 solo_observeTest(name, testCase) => solo_test(name, wrapMicrotask(testCase));