Make web_socket_ping_test pass on simulators, where it takes > 100ms to send data between sockets(!…

tests/standalone/io/web_socket_ping_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 testPing(int totalConnections) {
   HttpServer.bind('localhost', 0).then((server) {
     server.transform(new WebSocketTransformer()).listen((webSocket) {
-      webSocket.pingInterval = const Duration(milliseconds: 100);
+      webSocket.pingInterval = const Duration(milliseconds: 500);
       webSocket.drain();
     });
 
     var futures = [];
     for (int i = 0; i < totalConnections; i++) {
       futures.add(
           WebSocket.connect('ws://localhost:${server.port}').then((webSocket) {
-        webSocket.pingInterval = const Duration(milliseconds: 100);
+        webSocket.pingInterval = const Duration(milliseconds: 500);
         webSocket.drain();
-        new Timer(const Duration(seconds: 1), () {
+        new Timer(const Duration(seconds: 2), () {
           // Should not be closed yet.
           Expect.equals(null, webSocket.closeCode);
           webSocket.close();
         });
         return webSocket.done;
       }));
     }
     Future.wait(futures).then((_) => server.close());
   });
 }
 
 
 void main() {
   testPing(10);
 }