public MessageDescriptorBuilder <T> BytesArray(int fieldNum, Func <T, IEnumerable <byte[]> > valueGetter, Action <T, byte[]> oneValueSetter, Func <T, bool> hasValueFunc = null)
 {
     return(Add(FieldSetting <T> .CreateBytesArray(fieldNum, valueGetter, oneValueSetter, hasValueFunc)));
 }