[Sync] Move //components/sync_driver to //components/sync/driver.

components/sync_driver/device_info_util.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 COMPONENTS_SYNC_DRIVER_DEVICE_INFO_UTIL_H_
-#define COMPONENTS_SYNC_DRIVER_DEVICE_INFO_UTIL_H_
-
-#include <string>
-
-#include "base/time/time.h"
-
-namespace sync_pb {
-class DeviceInfoSpecifics;
-}
-
-namespace sync_driver {
-
-// This class contains constants and static helper functions that are shared
-// between DeviceInfoSyncService and DeviceInfoService.
-class DeviceInfoUtil {
- public:
-  // The prefix to be appended before the cache guid when creating tags. This is
-  // needed for backwards compatiblity with all old clients because we need to
-  // ensure everyone uses the same logic to generate the tag, so that everyone
-  // can independently hash the tag to the same value.
-  static const char kClientTagPrefix[];
-
-  // The delay between periodic updates to the entry corresponding to this
-  // device.
-  static const base::TimeDelta kPulseInterval;
-
-  // The amount of time a device can go without an updates before we consider it
-  // stale/inactive, and start ignoring it for active device counts.
-  static const base::TimeDelta kActiveThreshold;
-
-  // Determines the amount of time to wait before pulsing something with the
-  // given |last_update| timestamp. This uses the current time from |now| along
-  // with |kDeviceInfoPulseInterval|, and will never return a negative delay.
-  // The smallest delay this function will return, even for something extremely
-  // old will be a delay of 0 time units.
-  static base::TimeDelta CalculatePulseDelay(const base::Time last_update,
-                                             const base::Time now);
-
-  // Determines if the given |last_update| timestamp should be considerend
-  // active based on |kStaleDeviceInfoThreshold|, given the current time.
-  static bool IsActive(const base::Time last_update, const base::Time now);
-
-  // Formats ClientTag from DeviceInfoSpecifics.
-  static std::string SpecificsToTag(
-      const sync_pb::DeviceInfoSpecifics& specifics);
-
-  // Extracts cache_guid from ClientTag.
-  static std::string TagToCacheGuid(const std::string& tag);
-};
-
-}  // namespace sync_driver
-
-#endif  // COMPONENTS_SYNC_DRIVER_DEVICE_INFO_UTIL_H_