[Sync] Convert sync to a static library.

components/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 COMPONENTS_SYNC_API_ATTACHMENTS_ATTACHMENT_METADATA_H_
 #define COMPONENTS_SYNC_API_ATTACHMENTS_ATTACHMENT_METADATA_H_
 
 #include <stddef.h>
 
 #include <vector>
 
 #include "components/sync/api/attachments/attachment_id.h"
-#include "components/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 {
+class 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  // COMPONENTS_SYNC_API_ATTACHMENTS_ATTACHMENT_METADATA_H_