Manual revert of Timezone auto update option should be available by default.

chrome/browser/chromeos/login/ui/login_display_host_impl.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.
 
 #include "chrome/browser/chromeos/login/ui/login_display_host_impl.h"
 
 #include <vector>
 
 #include "ash/audio/sounds.h"
 #include "ash/desktop_background/desktop_background_controller.h"
@@ skipping 1105 matching lines @@
 }
 
 void LoginDisplayHostImpl::OnLoginPromptVisible() {
   if (!login_prompt_visible_time_.is_null())
     return;
   login_prompt_visible_time_ = base::TimeTicks::Now();
   TryToPlayStartupSound();
 }
 
 void LoginDisplayHostImpl::StartTimeZoneResolve() {
-  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
-          chromeos::switches::kDisableTimeZoneTrackingOption)) {
+  if (!base::CommandLine::ForCurrentProcess()->HasSwitch(
+          chromeos::switches::kEnableTimeZoneTrackingOption)) {
     return;
   }
 
   if (!g_browser_process->local_state()->GetBoolean(
           prefs::kResolveDeviceTimezoneByGeolocation)) {
     return;
   }
 
   if (system::HasSystemTimezonePolicy())
     return;
@@ skipping 128 matching lines @@
 
   locale_util::SwitchLanguageCallback callback(
       base::Bind(&OnLanguageSwitchedCallback, base::Passed(data.Pass())));
 
   // Load locale keyboards here. Hardware layout would be automatically enabled.
   locale_util::SwitchLanguage(
       locale, true, true /* login_layouts_only */, callback);
 }
 
 }  // namespace chromeos