Docserver: Make MockFileSystem not iterate over the entire file system as part

chrome/common/extensions/docs/server2/caching_file_system_test.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import os
 import sys
 import unittest
 
 from caching_file_system import CachingFileSystem
@@ skipping 119 matching lines @@
     file_system._read_object_store.Del('bob/bob1')
     futures = (file_system.ReadSingle('bob/bob1'),
                file_system.ReadSingle('bob/bob2'),
                file_system.ReadSingle('bob/bob3'))
     self.assertTrue(*mock_fs.CheckAndReset(read_count=3, stat_count=1))
     self.assertEqual(
         ('bob/bob1 contents', 'bob/bob2 contents', 'bob/bob3 contents'),
         tuple(future.Get() for future in futures))
     self.assertTrue(*mock_fs.CheckAndReset(read_resolve_count=3))
 
-    test_fs.IncrementStat(path='bob/')
+    test_fs.IncrementStat(path='bob/bob0')
     file_system = create_empty_caching_fs()
     self.assertEqual('bob/bob1 contents',
                      file_system.ReadSingle('bob/bob1').Get())
     self.assertEqual('bob/bob2 contents',
                      file_system.ReadSingle('bob/bob2').Get())
     self.assertEqual('bob/bob3 contents',
                      file_system.ReadSingle('bob/bob3').Get())
     self.assertTrue(*mock_fs.CheckAndReset(stat_count=1))
 
     file_system = create_empty_caching_fs()
@@ skipping 61 matching lines @@
         self.assertTrue(*mock_fs.CheckAndReset())
       run()
       run()
 
     run_expecting_stat('0')
     test_fs.IncrementStat()
     run_expecting_stat('1')
 
 if __name__ == '__main__':
   unittest.main()