Update mips test status files for new mips build slaves.

tests/standalone/io/signal_test_script.dart

 // Copyright (c) 2014, 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:io";
+import "dart:async";
 
 void main(args) {
   var signal;
+  var timeout = new Timer(new Duration(seconds: 25), () => exit(1));
   switch (args[0]) {
     case 'SIGHUP': signal = ProcessSignal.SIGHUP; break;
     case 'SIGINT': signal = ProcessSignal.SIGINT; break;
     case 'SIGTERM': signal = ProcessSignal.SIGTERM; break;
     case 'SIGUSR1': signal = ProcessSignal.SIGUSR1; break;
     case 'SIGUSR2': signal = ProcessSignal.SIGUSR2; break;
     case 'SIGWINCH': signal = ProcessSignal.SIGWINCH; break;
   }
   signal.watch().first.then((s) {
     if (signal != s) exit(1);
     if (signal.toString() != args[0]) exit(1);
     print('got signal');
+    timeout.cancel();
   });
   print("ready");
+  // This process should die if it never receives a signal.
 }