Write "logout-started" event on next boot.

chrome/browser/chromeos/preferences.cc

 // 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.
 
 #include "chrome/browser/chromeos/preferences.h"
 
 #include <vector>
 
 #include "ash/autoclick/autoclick_controller.h"
 #include "ash/magnifier/magnifier_constants.h"
@@ skipping 65 matching lines @@
   // no need to remove this shell observer.
   if (ash::Shell::HasInstance())
     ash::Shell::GetInstance()->RemoveShellObserver(this);
 }
 
 // static
 void Preferences::RegisterPrefs(PrefRegistrySimple* registry) {
   registry->RegisterBooleanPref(prefs::kOwnerPrimaryMouseButtonRight, false);
   registry->RegisterBooleanPref(prefs::kOwnerTapToClickEnabled, true);
   registry->RegisterBooleanPref(prefs::kVirtualKeyboardEnabled, false);
+  registry->RegisterStringPref(prefs::kLogoutStartedLast, std::string());
 }
 
 // static
 void Preferences::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* registry) {
   std::string hardware_keyboard_id;
   // TODO(yusukes): Remove the runtime hack.
   if (base::SysInfo::IsRunningOnChromeOS()) {
     DCHECK(g_browser_process);
     PrefService* local_state = g_browser_process->local_state();
@@ skipping 545 matching lines @@
   touch_hud_projection_enabled_.SetValue(enabled);
 }
 
 void Preferences::ActiveUserChanged(const User* active_user) {
   if (active_user != user_)
     return;
   ApplyPreferences(REASON_ACTIVE_USER_CHANGED, "");
 }
 
 }  // namespace chromeos