Deprecate NonThreadSafe in components/sync in favor of SequenceChecker.

components/sync/engine/attachments/on_disk_attachment_store.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_ENGINE_ATTACHMENTS_ON_DISK_ATTACHMENT_STORE_H_
 #define COMPONENTS_SYNC_ENGINE_ATTACHMENTS_ON_DISK_ATTACHMENT_STORE_H_
 
 #include <memory>
 #include <string>
 
 #include "base/files/file_path.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
-#include "base/threading/non_thread_safe.h"
+#include "base/sequence_checker.h"
 #include "components/sync/engine/attachments/attachment_store_backend.h"
 #include "components/sync/model/attachments/attachment.h"
 #include "components/sync/model/attachments/attachment_id.h"
 #include "components/sync/model/attachments/attachment_store.h"
 
 namespace attachment_store_pb {
 class RecordMetadata;
 }  // namespace attachment_store_pb
 
 namespace base {
 class SequencedTaskRunner;
 }  // namespace base
 
 namespace leveldb {
 class DB;
 }  // namespace leveldb
 
 namespace syncer {
 
 // On-disk implementation of AttachmentStore. Stores attachments in leveldb
 // database in |path| directory.
-class OnDiskAttachmentStore : public AttachmentStoreBackend,
-                              public base::NonThreadSafe {
+class OnDiskAttachmentStore : public AttachmentStoreBackend {
  public:
   // Constructs attachment store.
   OnDiskAttachmentStore(
       const scoped_refptr<base::SequencedTaskRunner>& callback_task_runner,
       const base::FilePath& path);
   ~OnDiskAttachmentStore() override;
 
   // AttachmentStoreBackend implementation.
   void Init(const AttachmentStore::InitCallback& callback) override;
   void Read(AttachmentStore::Component component,
@@ skipping 44 matching lines @@
       const AttachmentId& attachment_id);
   static std::string MakeMetadataKeyFromAttachmentId(
       const AttachmentId& attachment_id);
   static AttachmentMetadata MakeAttachmentMetadata(
       const AttachmentId& attachment_id,
       const attachment_store_pb::RecordMetadata& record_metadata);
 
   const base::FilePath path_;
   std::unique_ptr<leveldb::DB> db_;
 
+  SEQUENCE_CHECKER(sequence_checker_);
+
   DISALLOW_COPY_AND_ASSIGN(OnDiskAttachmentStore);
 };
 
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_ENGINE_ATTACHMENTS_ON_DISK_ATTACHMENT_STORE_H_