Add missing test_file_util_posix.cc file.

base/base.gyp

 # Copyright (c) 2009 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.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'includes': [
     '../build/common.gypi',
@@ skipping 223 matching lines @@
         'sys_string_conversions_mac.mm',
         'sys_string_conversions_win.cc',
         'system_monitor.cc',
         'system_monitor.h',
         'system_monitor_posix.cc',
         'system_monitor_win.cc',
         'task.h',
         'test_file_util.h',
         'test_file_util_linux.cc',
         'test_file_util_mac.cc',
+        'test_file_util_posix.cc',
         'test_file_util_win.cc',
         'thread.cc',
         'thread.h',
         'thread_collision_warner.cc',
         'thread_collision_warner.h',
         'thread_local.h',
         'thread_local_posix.cc',
         'thread_local_storage.h',
         'thread_local_storage_posix.cc',
         'thread_local_storage_win.cc',
@@ skipping 307 matching lines @@
           'target_name': 'debug_message',
           'type': 'executable',
           'sources': [
             'debug_message.cc',
           ],
         },
       ],
     }],
   ],
 }