Enable using the service library from dart:io applications.

runtime/bin/vmservice/client/lib/service_io.dart

Index: runtime/bin/vmservice/client/lib/service_io.dart
===================================================================
--- runtime/bin/vmservice/client/lib/service_io.dart	(revision 0)
+++ runtime/bin/vmservice/client/lib/service_io.dart	(revision 0)
@@ -0,0 +1,50 @@
+// Copyright (c) 2014, 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 service_io;
+
+import 'dart:io';
+
+import 'package:observatory/service_common.dart';
+
+// Export the service library.
+export 'package:observatory/service_common.dart';
+
+class _IOWebSocket implements CommonWebSocket {
+  WebSocket _webSocket;
+  
+  void connect(String address,
+               void onOpen(),
+               void onMessage(dynamic data),
+               void onError(),
+               void onClose()) {
+    WebSocket.connect(address).then((WebSocket socket) {
+      _webSocket = socket;
+      _webSocket.listen(
+          onMessage,
+          onError: (dynamic) => onError(),
+          onDone: onClose,
+          cancelOnError: true);
+      onOpen();
+    });
+  }
+  
+  bool get isOpen =>
+      (_webSocket != null) && (_webSocket.readyState == WebSocket.OPEN);
+  
+  void send(dynamic data) {
+    _webSocket.add(data);
+  }
+  
+  void close() {
+    _webSocket.close();
+  }
+}
+
+/// The [WebSocketVM] communicates with a Dart VM over WebSocket. The Dart VM
+/// can be embedded in Chromium or standalone. In the case of Chromium, we
+/// make the service requests via the Chrome Remote Debugging Protocol.
+class WebSocketVM extends CommonWebSocketVM {
+  WebSocketVM(WebSocketVMTarget target) : super(target, new _IOWebSocket());
+}