Upgrading tests with unittest deprecations

tests/isolate/cross_isolate_message_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.
 
 // Dart test program for testing that isolates can communicate to isolates
 // other than the main isolate.
 
 library CrossIsolateMessageTest;
 import 'dart:isolate';
 import 'package:unittest/unittest.dart';
@@ skipping 22 matching lines @@
 
 void crossIsolate2(SendPort toIsolate1) {
   toIsolate1.send(["fromIsolate2", 42]);
 }
 
 void main([args, port]) {
   if (testRemote(main, port)) return;
   test("send message cross isolates ", () {
     ReceivePort fromIsolate1 = new ReceivePort();
     Isolate.spawn(crossIsolate1, fromIsolate1.sendPort);
-    var done = expectAsync0((){});
+    var done = expectAsync((){});
     fromIsolate1.listen((msg) {
       switch (msg[0]) {
         case "ready1":
           SendPort toIsolate1 = msg[1];
           Isolate.spawn(crossIsolate2, toIsolate1);
           break;
         case "fromIsolate1":
           expect(msg[1], 100);
           fromIsolate1.close();
           break;
         default:
           fail("unreachable! Tag: ${msg[0]}");
       }
     }, onDone: done);
   });
 }