message: regex: implement size_hint for set match iterators
diff: @@ -295,6 +295,10 @@ impl Iterator for SetMatchesIntoIter {
  }
  }
  }
  +
  + fn size_hint(&self) -> (usize, Option<usize>) {
  + self.0.size_hint()
  + }
  }
  impl DoubleEndedIterator for SetMatchesIntoIter {
  @@ -331,6 +335,10 @@ impl<'a> Iterator for SetMatchesIter<'a> {
  }
  }
  }
  +
  + fn size_hint(&self) -> (usize, Option<usize>) {
  + self.0.size_hint()
  + }
  }
  impl<'a> DoubleEndedIterator for SetMatchesIter<'a> {
  