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

sync/engine/update_applicator.h

-// 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.
-//
-// An UpdateApplicator is used to iterate over a number of unapplied updates,
-// applying them to the client using the given syncer session.
-//
-// UpdateApplicator might resemble an iterator, but it actually keeps retrying
-// failed updates until no remaining updates can be successfully applied.
-
-#ifndef SYNC_ENGINE_UPDATE_APPLICATOR_H_
-#define SYNC_ENGINE_UPDATE_APPLICATOR_H_
-
-#include <stdint.h>
-
-#include <set>
-#include <vector>
-
-#include "base/macros.h"
-#include "sync/internal_api/public/engine/model_safe_worker.h"
-#include "sync/sessions/status_controller.h"
-#include "sync/syncable/syncable_id.h"
-
-namespace syncer {
-
-namespace sessions {
-class StatusController;
-}
-
-namespace syncable {
-class WriteTransaction;
-class Entry;
-}
-
-class ConflictResolver;
-class Cryptographer;
-
-class UpdateApplicator {
- public:
-  explicit UpdateApplicator(Cryptographer* cryptographer);
-  ~UpdateApplicator();
-
-  // Attempt to apply the specified updates.
-  void AttemptApplications(syncable::WriteTransaction* trans,
-                           const std::vector<int64_t>& handles);
-
-  int updates_applied() {
-    return updates_applied_;
-  }
-
-  int encryption_conflicts() {
-    return encryption_conflicts_;
-  }
-
-  int hierarchy_conflicts() {
-    return hierarchy_conflicts_;
-  }
-
-  const std::set<syncable::Id>& simple_conflict_ids() {
-    return simple_conflict_ids_;
-  }
-
- private:
-  // If true, AttemptOneApplication will skip over |entry| and return true.
-  bool SkipUpdate(const syncable::Entry& entry);
-
-  // Used to decrypt sensitive sync nodes.
-  Cryptographer* cryptographer_;
-
-  int updates_applied_;
-  int encryption_conflicts_;
-  int hierarchy_conflicts_;
-  std::set<syncable::Id> simple_conflict_ids_;
-
-  DISALLOW_COPY_AND_ASSIGN(UpdateApplicator);
-};
-
-}  // namespace syncer
-
-#endif  // SYNC_ENGINE_UPDATE_APPLICATOR_H_