[Sync] Move sessions/ to engine/cycle/ and rename things to match.

components/sync/sessions/update_counters.h

-// 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.
-
-#ifndef COMPONENTS_SYNC_SESSIONS_UPDATE_COUNTERS_H_
-#define COMPONENTS_SYNC_SESSIONS_UPDATE_COUNTERS_H_
-
-#include <memory>
-#include <string>
-
-#include "base/values.h"
-
-namespace syncer {
-
-// A class to maintain counts related to the update requests and responses for
-// a particular sync type.
-struct UpdateCounters {
-  UpdateCounters();
-  ~UpdateCounters();
-
-  std::unique_ptr<base::DictionaryValue> ToValue() const;
-  std::string ToString() const;
-
-  int num_updates_received;
-  int num_reflected_updates_received;
-  int num_tombstone_updates_received;
-
-  int num_updates_applied;
-  int num_hierarchy_conflict_application_failures;
-  int num_encryption_conflict_application_failures;
-
-  int num_server_overwrites;
-  int num_local_overwrites;
-};
-
-}  // namespace syncer
-
-#endif  // COMPONENTS_SYNC_SESSIONS_UPDATE_COUNTERS_H_