Observatory now uses websockets to communicate with the vm.

tests/standalone/vmservice/test_helper.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 vmservice_test_helper;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 import 'package:expect/expect.dart';
@@ skipping 21 matching lines @@
   void complete() {
     _completer.complete(this);
   }
 
   Future get completed => _completer.future;
 
   // Must call complete.
   void onResponse(var seq, Map response);
   void runTest();
 
-  Future sendMessage(var seq, List<String> path) {
+  Future sendMessage(var seq, String request) {
     var map = {
       'seq': seq,
-      'path': path
+      'request': request
     };
     var message = JSON.encode(map);
     _socket.add(message);
     return _completer.future;
   }
 }
 
 abstract class VmServiceRequestHelper {
   final Uri uri;
   final HttpClient client;
@@ skipping 210 matching lines @@
       });
     });
     return Future.wait(requests).then((a) {
       a.forEach((FieldRequestHelper field) {
         fields[field.field['user_name']] = field.field;
       });
       return this;
     });
   }
 }