Fix GN bootstrap

tools/gn/bootstrap/bootstrap.py

 #!/usr/bin/env python
 # Copyright 2014 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.
 
 # This file isn't officially supported by the Chromium project. It's maintained
 # on a best-effort basis by volunteers, so some things may be broken from time
 # to time. If you encounter errors, it's most often due to files in base that
 # have been added or moved since somebody last tried this script. Generally
 # such errors are easy to diagnose.
@@ skipping 409 matching lines @@
       'base/path_service.cc',
       'base/pending_task.cc',
       'base/pickle.cc',
       'base/process/kill.cc',
       'base/process/process_iterator.cc',
       'base/process/process_metrics.cc',
       'base/profiler/scoped_profile.cc',
       'base/profiler/scoped_tracker.cc',
       'base/profiler/tracked_time.cc',
       'base/run_loop.cc',
+      'base/sequence_token.cc',
       'base/sequence_checker_impl.cc',
       'base/sequenced_task_runner.cc',
       'base/sha1.cc',
       'base/strings/pattern.cc',
       'base/strings/string_number_conversions.cc',
       'base/strings/string_piece.cc',
       'base/strings/string_split.cc',
       'base/strings/string_util.cc',
       'base/strings/string_util_constants.cc',
       'base/strings/stringprintf.cc',
       'base/strings/utf_string_conversion_utils.cc',
       'base/strings/utf_string_conversions.cc',
-      'base/synchronization/cancellation_flag.cc',
+      'base/synchronization/atomic_flag.cc',
       'base/synchronization/lock.cc',
       'base/sys_info.cc',
       'base/task_runner.cc',
       'base/third_party/dmg_fp/dtoa_wrapper.cc',
       'base/third_party/dmg_fp/g_fmt.cc',
       'base/third_party/icu/icu_utf.cc',
       'base/third_party/nspr/prtime.cc',
       'base/threading/non_thread_safe_impl.cc',
       'base/threading/post_task_and_reply_impl.cc',
       'base/threading/sequenced_task_runner_handle.cc',
@@ skipping 271 matching lines @@
     cmd.append('-v')
   cmd.append('gn')
   check_call(cmd)
 
   if not options.debug and not is_win:
     check_call(['strip', os.path.join(build_dir, 'gn')])
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv[1:]))