Service isolate rework take 2

runtime/bin/vmservice/vmservice_io.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_io;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 import 'dart:isolate';
 import 'dart:vmservice';
 
+part 'loader.dart';
 part 'resources.dart';
 part 'server.dart';
 
 // The TCP ip/port that the HTTP server listens on.
 int _port;
 String _ip;
 // Should the HTTP server auto start?
 bool _autoStart;
 
 bool _isWindows = false;
 
+var _signalWatch;
+
 // HTTP servr.
 Server server;
 Future<Server> serverFuture;
 
 void _bootServer() {
   // Load resources.
   _triggerResourceLoad();
   // Lazily create service.
   var service = new VMService();
   // Lazily create server.
@@ skipping 13 matching lines @@
     _bootServer();
   }
   // Toggle HTTP server.
   if (server.running) {
     serverFuture = server.shutdown(true).then(_clearFuture);
   } else {
     serverFuture = server.startup().then(_clearFuture);
   }
 }
 
-void _registerSignalHandler(Stream signalWatch(ProcessSignal signal)) {
+void _registerSignalHandler() {
   if (_isWindows) {
     // Cannot register for signals on Windows.
     return;
   }
-  signalWatch(ProcessSignal.SIGQUIT).listen(_onSignal);
+  _signalWatch(ProcessSignal.SIGQUIT).listen(_onSignal);
 }
 
-main(Stream signalWatch(ProcessSignal signal)) {
+const _shortDelay = const Duration(milliseconds: 10);
+
+main() {
   if (_autoStart) {
     _bootServer();
     server.startup();
+    // It's just here to push an event on the event loop so that we invoke the
+    // scheduled microtasks.
+    Timer.run(() {});
   }
-  _registerSignalHandler(signalWatch);
+  scriptLoadPort.handler = _processLoadRequest;
+  // Register signal handler after a small delay to avoid stalling main
+  // isolate startup.
+  new Timer(_shortDelay, _registerSignalHandler);
+  return scriptLoadPort;
 }