Remove old isolate API and update all code in the repository to use

tests/standalone/io/echo_server_stream_test.dart

Index: tests/standalone/io/echo_server_stream_test.dart
diff --git a/tests/standalone/io/echo_server_stream_test.dart b/tests/standalone/io/echo_server_stream_test.dart
index 775795c7bb8adc6353e80b95d1b1918a2103c4eb..4581126b074573cdd2a02929b7c4aaeff2ec53fb 100644
--- a/tests/standalone/io/echo_server_stream_test.dart
+++ b/tests/standalone/io/echo_server_stream_test.dart
@@ -27,10 +27,8 @@ class EchoServerGame {
     for (int i = 0; i < MSGSIZE; i++) {
       _buffer[i] = FIRSTCHAR + i;
     }
-    new EchoServer().spawn().then((SendPort port) {
-      _sendPort = port;
-      start();
-    });
+    _sendPort = spawnFunction(startEchoServer);
+    start();
   }
 
   void sendData() {
@@ -135,6 +133,14 @@ class EchoServerGame {
 }
 
 
+void startEchoServer() {
+  var server = new EchoServer();
+  port.receive((message, SendPort replyTo) {
+    server.dispatch(message, replyTo);
+  });
+}
+
+
 class EchoServer extends TestingServer {
 
   static final int MSGSIZE = EchoServerGame.MSGSIZE;