ChromeOS: Add SystemTimezoneAutomaticDetection policy.

chrome/browser/about_flags.cc

Index: chrome/browser/about_flags.cc
diff --git a/chrome/browser/about_flags.cc b/chrome/browser/about_flags.cc
index 320b7ec9e86dfd44c205cdba1cf0b15b9017449f..ec70ebd168d9c0d5b037275c7c4a67619b63efd7 100644
--- a/chrome/browser/about_flags.cc
+++ b/chrome/browser/about_flags.cc
@@ -1825,6 +1825,11 @@ const FeatureEntry kFeatureEntries[] = {
      {"opt-in-ime-menu", IDS_FLAGS_ENABLE_IME_MENU_NAME,
      IDS_FLAGS_ENABLE_IME_MENU_DESCRIPTION, kOsCrOS,
      FEATURE_VALUE_TYPE(features::kOptInImeMenu)},
+    {"enable-system-timezone-automatic-detection",
+     IDS_FLAGS_ENABLE_SYSTEM_TIMEZONE_AUTOMATIC_DETECTION_NAME,
+     IDS_FLAGS_ENABLE_SYSTEM_TIMEZONE_AUTOMATIC_DETECTION_DESCRIPTION, kOsCrOS,
+     SINGLE_VALUE_TYPE(
+         chromeos::switches::kEnableSystemTimezoneAutomaticDetectionPolicy)},
 #endif
     // NOTE: Adding new command-line switches requires adding corresponding
     // entries to enum "LoginCustomFlags" in histograms.xml. See note in