Add zone support to streams.

tests/lib/async/catch_errors20_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';
+
+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 = [];
+  // Test that nested stream (from `catchErrors`) that is delayed by a future
+  // is waited for.
+  catchErrors(() {
+    catchErrors(() {
+      new Future.error(499);
+      new Future.delayed(const Duration(milliseconds: 20), () {
+        events.add(42);
+      });
+    }).listen(events.add,
+              onDone: () { events.add("done"); });
+    throw "foo";
+  }).listen((x) { events.add("outer: $x"); },
+            onDone: () {
+              Expect.listEquals(["outer: foo",
+                                 499,
+                                 42,
+                                 "done",
+                                ],
+                                events);
+              port.close();
+            });
+}