code: private Versioned<Collection<byte[]>> toVersioned(
        MapEntryValues value) {
      return value == null
          ? new Versioned<>(Collections.emptyList(), -1)
          : new Versioned<>(value.values(), value.version());
    }
docs: Utility for turning a {@code MapEntryValue} to {@code Versioned}.
  
  @param value map entry value
  @return versioned instance or an empty list versioned -1 if argument is
  null