Rework Timer interface.

tests/standalone/io/http_server_early_server_close_test.dart

 // Copyright (c) 2012, 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.
 
 import "dart:async";
 import "dart:io";
 import "dart:isolate";
 
 class Server {
   Server() {
     HttpServer server = new HttpServer();
     server.listen("127.0.0.1", 0);
     port = server.port;
     server.defaultRequestHandler =
         (HttpRequest request, HttpResponse response) {
-          new Timer(0, (timer) => server.close());
+          Timer.run(server.close);
         };
     server.onError = (e) {
       Expect.fail("No server errors expected: $e");
     };
   }
   int port;
 }
 
 class Client {
   Client(int port) {
     ReceivePort r = new ReceivePort();
     HttpClient client = new HttpClient();
     HttpClientConnection c = client.get("127.0.0.1", port, "/");
     c.onRequest = (HttpClientRequest request) {
       request.outputStream.close();
     };
     c.onResponse = (HttpClientResponse response) {
       Expect.fail("Response should not be given, as not data was returned.");
     };
     c.onError = (e) {
       r.close();
     };
   }
 }
 
 main() {
   Server server = new Server();
   new Client(server.port);
 }