Revert "Zone support for Futures."

tests/lib/async/catch_errors21_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:expect/expect.dart";
-import 'dart:async';
-import 'dart:isolate';
-import 'catch_errors.dart';
-
-main() {
-  // We keep a ReceivePort open until all tests are done. This way the VM will
-  // hang if the callbacks are not invoked and the test will time out.
-  var port = new ReceivePort();
-  var events = [];
-  var controller = new StreamController();
-  // Test that stream errors, as a result of bad user-code (`map`) are correctly
-  // caught by `catchErrors`. Note that the values are added outside both
-  // `catchErrors`, but since the `listen` happens in the most nested
-  // `catchErrors` it is caught there.
-  catchErrors(() {
-    catchErrors(() {
-      controller.stream.map((x) { throw x; }).listen((x) {
-        // Should not happen.
-        events.add("bad: $x");
-      });
-    }).listen((x) { events.add("caught: $x"); },
-              onDone: () { events.add("done"); });
-  }).listen((x) { events.add("outer: $x"); },
-            onDone: () {
-              Expect.listEquals(["caught: 1",
-                                 "caught: 2",
-                                 "caught: 3",
-                                 "caught: 4",
-                                 "done",
-                                ],
-                                events);
-              port.close();
-            });
-  [1, 2, 3, 4].forEach(controller.add);
-  controller.close();
-}