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

chrome/browser/about_flags.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/about_flags.h"
 
 #include <iterator>
 #include <map>
 #include <set>
 #include <utility>
@@ skipping 2127 matching lines @@
   {
     "enable-harfbuzz-rendertext",
     IDS_FLAGS_ENABLE_HARFBUZZ_RENDERTEXT_NAME,
     IDS_FLAGS_ENABLE_HARFBUZZ_RENDERTEXT_DESCRIPTION,
     kOsMac,
     SINGLE_VALUE_TYPE(switches::kEnableHarfBuzzRenderText)
   },
 #endif  // defined(OS_MACOSX)
 #if defined(OS_CHROMEOS)
   {
-    "disable-timezone-tracking",
-    IDS_FLAGS_DISABLE_RESOLVE_TIMEZONE_BY_GEOLOCATION_NAME,
-    IDS_FLAGS_DISABLE_RESOLVE_TIMEZONE_BY_GEOLOCATION_DESCRIPTION,
+    "enable-timezone-tracking",
+    IDS_FLAGS_ENABLE_RESOLVE_TIMEZONE_BY_GEOLOCATION_NAME,
+    IDS_FLAGS_ENABLE_RESOLVE_TIMEZONE_BY_GEOLOCATION_DESCRIPTION,
     kOsCrOS,
-    SINGLE_VALUE_TYPE(chromeos::switches::kDisableTimeZoneTrackingOption)
+    SINGLE_VALUE_TYPE(chromeos::switches::kEnableTimeZoneTrackingOption)
   },
 #endif  // defined(OS_CHROMEOS)
 
   // NOTE: Adding new command-line switches requires adding corresponding
   // entries to enum "LoginCustomFlags" in histograms.xml. See note in
   // histograms.xml and don't forget to run AboutFlagsHistogramTest unit test.
 };
 
 const Experiment* experiments = kExperiments;
 size_t num_experiments = arraysize(kExperiments);
@@ skipping 561 matching lines @@
 }
 
 const Experiment* GetExperiments(size_t* count) {
   *count = num_experiments;
   return experiments;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags