Replace deprecated base::NonThreadSafe in chrome in favor of SequenceChecker.

chrome/browser/process_singleton_posix.cc

 // 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.
 
 // On Linux, when the user tries to launch a second copy of chrome, we check
 // for a socket in the user's profile directory.  If the socket file is open we
 // send a message to the first chrome browser process with the current
 // directory and second process command line flags.  The second process then
 // exits.
 //
@@ skipping 736 matching lines @@
       watcher_(new LinuxWatcher(this)) {
   socket_path_ = user_data_dir.Append(chrome::kSingletonSocketFilename);
   lock_path_ = user_data_dir.Append(chrome::kSingletonLockFilename);
   cookie_path_ = user_data_dir.Append(chrome::kSingletonCookieFilename);
 
   kill_callback_ = base::Bind(&ProcessSingleton::KillProcess,
                               base::Unretained(this));
 }
 
 ProcessSingleton::~ProcessSingleton() {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
 }
 
 ProcessSingleton::NotifyResult ProcessSingleton::NotifyOtherProcess() {
   return NotifyOtherProcessWithTimeout(
       *base::CommandLine::ForCurrentProcess(), kRetryAttempts,
       base::TimeDelta::FromSeconds(kTimeoutInSeconds), true);
 }
 
 ProcessSingleton::NotifyResult ProcessSingleton::NotifyOtherProcessWithTimeout(
     const base::CommandLine& cmd_line,
@@ skipping 364 matching lines @@
       case EPERM:
         action = TERMINATE_NOT_ENOUGH_PERMISSIONS;
         break;
       default:
         action = TERMINATE_FAILED;
         break;
     }
   }
   SendRemoteProcessInteractionResultHistogram(action);
 }