Make it possible to share the embedder's dart sources for the vmservice

runtime/bin/vmservice/server.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.
 
 part of vmservice_io;
 
 class WebSocketClient extends Client {
   static const int PARSE_ERROR_CODE = 4000;
   static const int BINARY_MESSAGE_ERROR_CODE = 4001;
   static const int NOT_MAP_ERROR_CODE = 4002;
@@ skipping 139 matching lines @@
     // HTTP based service request.
     try {
       var client = new HttpRequestClient(request, _service);
       var message = new Message.fromUri(client, request.uri);
       client.onMessage(null, message);
     } catch (e) {
       print('Unexpected error processing HTTP request uri: '
             '${request.uri}\n$e\n');
       rethrow;
     }
-
   }
 
   Future startup() {
     if (_server != null) {
       // Already running.
       return new Future.value(this);
     }
 
+    var address = new InternetAddress(_ip);
     // Startup HTTP server.
-    return HttpServer.bind(_ip, _port).then((s) {
+    return HttpServer.bind(address, _port).then((s) {
       _server = s;
-      _server.listen(_requestHandler);
+      _server.listen(_requestHandler, cancelOnError: true);
       var ip = _server.address.address.toString();
+      var port = _server.port.toString();
       if (_displayMessages) {
-        var port = _server.port.toString();
         print('Observatory listening on http://$ip:$port');
       }
       // Server is up and running.
       _notifyServerState(ip, _server.port);
+      onServerAddressChange('http://$ip:$port');
       return this;
     }).catchError((e, st) {
       print('Could not start Observatory HTTP server:\n$e\n$st\n');
       _notifyServerState("", 0);
+      onServerAddressChange(null);
       return this;
     });
   }
 
-  close(bool force) {
+  Future cleanup(bool force) {
     if (_server == null) {
       return new Future.value(null);
     }
     return _server.close(force: force);
   }
 
   Future shutdown(bool forced) {
     if (_server == null) {
       // Not started.
       return new Future.value(this);
     }
 
     // Force displaying of status messages if we are forcibly shutdown.
     _displayMessages = _displayMessages || forced;
 
     // Shutdown HTTP server and subscription.
     var ip = _server.address.address.toString();
     var port = _server.port.toString();
-    return close(forced).then((_) {
+    return cleanup(forced).then((_) {
       if (_displayMessages) {
         print('Observatory no longer listening on http://$ip:$port');
       }
       _server = null;
       _notifyServerState("", 0);
+      onServerAddressChange(null);
       return this;
     }).catchError((e, st) {
       _server = null;
       print('Could not shutdown Observatory HTTP server:\n$e\n$st\n');
       _notifyServerState("", 0);
+      onServerAddressChange(null);
       return this;
     });
   }
 
 }
 
 void _notifyServerState(String ip, int port)
     native "VMServiceIO_NotifyServerState";