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

sync/api/attachments/attachment_metadata.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 SYNC_API_ATTACHMENTS_ATTACHMENT_METADATA_H_
-#define SYNC_API_ATTACHMENTS_ATTACHMENT_METADATA_H_
-
-#include <stddef.h>
-
-#include <vector>
-
-#include "sync/api/attachments/attachment_id.h"
-#include "sync/base/sync_export.h"
-
-namespace syncer {
-
-// This class represents immutable Attachment metadata.
-//
-// It is OK to copy and return AttachmentMetadata by value.
-class SYNC_EXPORT AttachmentMetadata {
- public:
-  AttachmentMetadata(const AttachmentId& id, size_t size);
-  ~AttachmentMetadata();
-
-  // Default copy and assignment are welcome.
-
-  // Returns this attachment's id.
-  const AttachmentId& GetId() const;
-
-  // Returns this attachment's size in bytes.
-  size_t GetSize() const;
-
- private:
-  // TODO(maniscalco): Reconcile AttachmentMetadata and
-  // AttachmentId. AttachmentId knows the size of the attachment so
-  // AttachmentMetadata may not be necessary (crbug/465375).
-  AttachmentId id_;
-  size_t size_;
-};
-
-typedef std::vector<syncer::AttachmentMetadata> AttachmentMetadataList;
-
-}  // namespace syncer
-
-#endif  // SYNC_API_ATTACHMENTS_ATTACHMENT_METADATA_H_