Very simple version of Isolates.

tests/isolate/isolate_negative_test.dart

Index: tests/isolate/isolate_negative_test.dart
diff --git a/tests/isolate/isolate_negative_test.dart b/tests/isolate/isolate_negative_test.dart
index 7f753f2cfec7b8cf8578c95c4c9a3047faa3a571..e40d23e995d9f303bea93fd33cc778f941628e8d 100644
--- a/tests/isolate/isolate_negative_test.dart
+++ b/tests/isolate/isolate_negative_test.dart
@@ -9,16 +9,15 @@ import "package:expect/expect.dart";
 import 'dart:isolate';
 import '../../pkg/unittest/lib/unittest.dart';
 
-void entry() {
-  port.receive((ignored, replyTo) {
-    replyTo.send("foo", null);
-  });
+void entry(SendPort replyTo) {
+  replyTo.send("foo");
 }
 
 main() {
   test("ensure isolate code is executed", () {
-    SendPort port = spawnFunction(entry);
-    port.call("foo").then(expectAsync1((message) {
+    ReceivePort response = new ReceivePort();
+    Isolate.spawn(entry, response.sendPort);
+    response.first.then(expectAsync1((message) {
       expect("Expected fail", isTrue);   // <=-------- Should fail here.
     }));
   });