Add zone support to streams.

tests/lib/async/catch_errors25_test.dart

Index: tests/lib/async/catch_errors25_test.dart
diff --git a/tests/lib/async/catch_errors4_test.dart b/tests/lib/async/catch_errors25_test.dart
similarity index 54%
copy from tests/lib/async/catch_errors4_test.dart
copy to tests/lib/async/catch_errors25_test.dart
index d5681848c3d8eac0b910cfee4af578b326954323..22fa8f0e8242e767ec73b6ba3d6be8f3c9448c04 100644
--- a/tests/lib/async/catch_errors4_test.dart
+++ b/tests/lib/async/catch_errors25_test.dart
@@ -11,20 +11,16 @@ main() {
   // hang if the callbacks are not invoked and the test will time out.
   var port = new ReceivePort();
   var events = [];
-  // Test that synchronous errors inside a `catchErrors` are caught.
+  StreamController controller;
+  // Test multiple subscribers of an asBroadcastStream inside the same
+  // `catchErrors`.
   catchErrors(() {
-    events.add("catch error entry");
-    throw "catch error";
-  }).listen((x) {
-      events.add(x);
-    },
-    onDone: () {
-      Expect.listEquals(["catch error entry",
-                         "main exit",
-                         "catch error",
-                         ],
-                         events);
-      port.close();
-    });
-  events.add("main exit");
+    var stream = new Stream.fromIterable([1, 2]).asBroadcastStream();
+    stream.listen(events.add);
+    stream.listen(events.add);
+  }).listen((x) { events.add("outer: $x"); },
+            onDone: () {
+              Expect.listEquals([1, 1, 2, 2], events);
+              port.close();
+            });
 }