ChromeOS: Add SystemTimezoneAutomaticDetection policy.

chrome/browser/chromeos/system/timezone_resolver_manager.h

+// Copyright 2016 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.
+
+#ifndef CHROME_BROWSER_CHROMEOS_SYSTEM_TIMEZONE_RESOLVER_MANAGER_H_
+#define CHROME_BROWSER_CHROMEOS_SYSTEM_TIMEZONE_RESOLVER_MANAGER_H_
+
+#include "base/macros.h"
+#include "chromeos/timezone/timezone_resolver.h"
+#include "components/prefs/pref_change_registrar.h"
+
+class PrefService;
+
+namespace chromeos {
+namespace system {
+
+class TimeZoneResolverManager : public TimeZoneResolver::Delegate {
+ public:
+  TimeZoneResolverManager();
+  ~TimeZoneResolverManager() override;
+
+  // This sets primary_user_prefs_.
+  void SetPrimaryUserPrefs(PrefService* pref_service);
+
+  // TimeZoneResolver::Delegate overrides:
+  bool ShouldSendWiFiGeolocationData() override;
+
+  // Starts or stops TimezoneResolver according to currect settings.
+  void UpdateTimezoneResolver();
+
+  // Returns true if result of timezone resolve should be applied to
+  // system timezone (preferences might have changed since request was started).
+  bool ShouldApplyResolvedTimezone();
+
+ private:
+  // Returns true if TimeZoneResolver should be running and taking in account
+  // all configuration data.
+  bool IsTimeZoneResolverShouldBeRunnig();
+
+  // This is non-null only after user logs in.
+  PrefService* primary_user_prefs_;
+
+  // This is used to subscribe to policy preference.
+  PrefChangeRegistrar local_state_pref_change_registrar_;
+
+  DISALLOW_COPY_AND_ASSIGN(TimeZoneResolverManager);
+};
+
+}  // namespace system
+}  // namespace chromeos
+
+#endif  // CHROME_BROWSER_CHROMEOS_SYSTEM_TIMEZONE_RESOLVER_MANAGER_H_