isolates refactor: this change introduces 'dart:isolate' as a library. This is a

tests/corelib/src/FuturesTest.dart

 // Copyright (c) 2011, 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("FuturesTest");
+#import("dart:isolate");
+
 Future testWaitEmpty() {
   List<Future> futures = new List<Future>();
   return Futures.wait(futures);
 }
 
 Future testCompleteAfterWait() {
   List<Future> futures = new List<Future>();
   Completer<Object> c = new Completer<Object>();
   futures.add(c.future);
   Future future = Futures.wait(futures);
@@ skipping 17 matching lines @@
   futures.add(testCompleteBeforeWait());
 
   // Use a receive port for blocking the test. 
   // Note that if the test fails, the program will not end.
   ReceivePort port = new ReceivePort();
   Futures.wait(futures).then((List list) {
     Expect.equals(3, list.length);
     port.close();
   });
 }