Remove use of deprecated mirror API from pkg/unittest.

pkg/unittest/test/mirror_matchers_test.dart

 // Copyright (c) 2012, 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.
 
 import 'package:unittest/unittest.dart';
 import 'package:unittest/mirror_matchers.dart';
 
 import 'test_utils.dart';
 
+class C {
+  var instanceField = 1;
+  get instanceGetter => 2;
+  static var staticField = 3;
+  static get staticGetter => 4;
+}
+
 void main() {
 
   initUtils();
 
   test('hasProperty', () {
     var foo = [3];
     shouldPass(foo, hasProperty('length', 1));
     shouldFail(foo, hasProperty('foo'), 'Expected: has property "foo" '
         'Actual: [3] '
         'Which: has no property named "foo"');
     shouldFail(foo, hasProperty('length', 2),
         'Expected: has property "length" which matches <2> '
         'Actual: [3] '
         'Which: has property "length" with value <1>');
+    var c = new C();
+    shouldPass(c, hasProperty('instanceField', 1));
+    shouldPass(c, hasProperty('instanceGetter', 2));
+    shouldFail(c, hasProperty('staticField'), 
+        'Expected: has property "staticField" '
+        'Actual: <Instance of \'C\'> '
+        'Which: has a member named "staticField",'
+        ' but it is not an instance property');
+    shouldFail(c, hasProperty('staticGetter'),
+        'Expected: has property "staticGetter" '
+        'Actual: <Instance of \'C\'> '
+        'Which: has a member named "staticGetter",'
+        ' but it is not an instance property');
   });
 }