Upgrading tests with unittest deprecations

tests/lib/async/multiple_timer_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.
 
 library multiple_timer_test;
 
 import 'dart:async';
 import '../../../pkg/unittest/lib/unittest.dart';
 
 const Duration TIMEOUT1 = const Duration(seconds: 1);
@@ skipping 45 matching lines @@
     }
 
     _order = new List<int>(4);
     _order[0] = 2;
     _order[1] = 0;
     _order[2] = 3;
     _order[3] = 1;
     _message = 0;
 
     _stopwatch1.start();
-    new Timer(TIMEOUT1, expectAsync0(timeoutHandler1));
+    new Timer(TIMEOUT1, expectAsync(timeoutHandler1));
     _stopwatch2.start();
-    new Timer(TIMEOUT2, expectAsync0(timeoutHandler2));
+    new Timer(TIMEOUT2, expectAsync(timeoutHandler2));
     _stopwatch3.start();
-    new Timer(TIMEOUT3, expectAsync0(timeoutHandler3));
+    new Timer(TIMEOUT3, expectAsync(timeoutHandler3));
     _stopwatch4.start();
-    new Timer(TIMEOUT4, expectAsync0(timeoutHandler4));
+    new Timer(TIMEOUT4, expectAsync(timeoutHandler4));
   });
 }