Increase timeout for http_response_deadline_test, to make it stable on DebugSIMARM.

tests/standalone/io/http_response_deadline_test.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.
 //
 // VMOptions=
 // VMOptions=--short_socket_read
 // VMOptions=--short_socket_write
 // VMOptions=--short_socket_read --short_socket_write
 
 import "package:expect/expect.dart";
 import "dart:async";
 import "dart:io";
 
 void testSimpleDeadline(int connections) {
   HttpServer.bind('localhost', 0).then((server) {
     server.listen((request) {
-      request.response.deadline = const Duration(seconds: 10);
+      request.response.deadline = const Duration(seconds: 1000);
       request.response.write("stuff");
       request.response.close();
     });
 
     var futures = [];
     var client = new HttpClient();
     for (int i = 0; i < connections; i++) {
       futures.add(client.get('localhost', server.port, '/')
           .then((request) => request.close())
           .then((response) => response.drain()));
@@ skipping 55 matching lines @@
     Future.wait(futures).then((_) => server.close());
   });
 }
 
 void main() {
   testSimpleDeadline(10);
   testExceedDeadline(10);
   testDeadlineAndDetach(10);
 }