message: Avoid wrapping Cloner around empty iterator
diff: @@ -40,9 +40,7 @@ impl ReadonlyStorage for MemoryStorage {
  // However, this cases represent just empty range and we treat it as such.
  match (bounds.start_bound(), bounds.end_bound()) {
  (Bound::Included(start), Bound::Excluded(end)) if start > end => {
  - return Ok(Box::new(Cloner {
  - iter: iter::empty(),
  - }));
  + return Ok(Box::new(iter::empty()));
  }
  _ => {}
  }
  