Add library tags so that the tests work in dartium.

tests/isolate/global_error_handler_stream2_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.
 
+library test;
+
 import 'dart:async';
 import 'dart:isolate';
 
 runTest() {
   IsolateSink mainIsolate;
   stream.listen((msg) {
     mainIsolate = msg;
     throw new RuntimeError("ignore exception");
   }, onDone: () {
     mainIsolate.add("received done");
@@ skipping 15 matching lines @@
 
   var box = new MessageBox();
   IsolateSink otherIsolate = streamSpawnFunction(runTest, globalErrorHandler);
   otherIsolate.add(box.sink);
   otherIsolate.close();
   box.stream.single.then((msg) {
     Expect.equals("received done", msg);
     timer.cancel();
   });
 }