Expose Zones.

tests/lib/async/run_zoned8_test.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.
 
 import 'package:async_helper/async_helper.dart';
 import "package:expect/expect.dart";
 import 'dart:async';
 import 'catch_errors.dart';
 
 main() {
   asyncStart();
+  Completer done = new Completer();
+
   var events = [];
   // Test runZoned with periodic Timers.
-  runZonedExperimental(() {
+  runZoned(() {
     int counter = 0;
     new Timer.periodic(const Duration(milliseconds: 50), (timer) {
-      if (counter == 1) timer.cancel();
+      if (counter == 1) {
+        timer.cancel();
+        done.complete(true);
+      }
       counter++;
       events.add(counter);
       throw counter;
     });
-  }, onError: (e) {
-       events.add("error: $e");
-     },
-     onDone: () {
-         Expect.listEquals([
-                           "main exit",
-                           1, "error: 1", 2, "error: 2",
-                           ],
-                           events);
-         asyncEnd();
-       });
+  }, onError: (e) { events.add("error: $e"); });
+
+  done.future.whenComplete(() {
+    Expect.listEquals([
+                      "main exit",
+                      1, "error: 1", 2, "error: 2",
+                      ],
+                      events);
+    asyncEnd();
+  });
   events.add("main exit");
 }