Make isolate tests work on drt (and hopefully dartium).

tests/isolate/request_reply_test.dart

Index: tests/isolate/request_reply_test.dart
diff --git a/tests/isolate/request_reply_test.dart b/tests/isolate/request_reply_test.dart
index f70fb5a9b1b73857407f186fa02e3ffef1062e08..713f7bb97376c7498c03f58a05226b38470b0d1e 100644
--- a/tests/isolate/request_reply_test.dart
+++ b/tests/isolate/request_reply_test.dart
@@ -5,7 +5,8 @@
 library RequestReplyTest;
 
 import 'dart:isolate';
-import '../../pkg/unittest/lib/unittest.dart';
+import 'package:unittest/unittest.dart';
+import "remote_unittest_helper.dart";
 
 void entry(initPort) {
   ReceivePort port = new ReceivePort();
@@ -18,7 +19,8 @@ void entry(initPort) {
   });
 }
 
-void main() {
+void main([args, port]) {
+  if (testRemote(main, port)) return;
   test("send", () {
     ReceivePort init = new ReceivePort();
     Isolate.spawn(entry, init.sendPort);