Increase number of files created, to avoid flakyness on linux.

tests/standalone/io/directory_list_pause_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.
 
 import "package:expect/expect.dart";
 import "dart:async";
 import "dart:io";
 import "dart:isolate";
 
 
 void testPauseList() {
   var keepAlive = new ReceivePort();
   new Directory("").createTemp().then((d) {
-    // Linux reads 2K at a time.
-    int total = 2 * 1024 + 1;
+    // Linux reads 2K at a time, so be sure to be >>.
+    int total = 4 * 1024 + 1;
     for (int i = 0; i < total; i++) {
       new File("${d.path}/$i").createSync();
     }
     bool first = true;
     var subscription;
     int count = 0;
     subscription = d.list().listen((file) {
       if (first) {
         first = false;
         subscription.pause();
         Timer.run(() {
           for (int i = 0; i < total; i++) {
             new File("${d.path}/$i").deleteSync();
           }
           subscription.resume();
         });
       }
       count++;
     }, onDone: () {
-      Expect.isTrue(count < total);
+      Expect.notEquals(total, count);
       keepAlive.close();
       d.delete().then((ignore) => keepAlive.close());
     });
   });
 }
 
 void main() {
   testPauseList();
 }