message: Specify WriteFlags explicitly
diff: @@ -303,7 +303,7 @@ impl Storage {
  // versions - they were most likely created before the upgrade and should be
  // reverted.
  if block.era_id() >= invalid_era && block.protocol_version() < protocol_version {
  - cursor.del(Default::default())?;
  + cursor.del(WriteFlags::empty())?;
  continue;
  }
  }
  