Follow up to #21062. Was going to be a part of #20833 but I’m trying to break it down as much as possible.
- Make members const (https://github.com/bitcoin/bitcoin/pull/21062#discussion_r573659273)
- List fee units (https://github.com/bitcoin/bitcoin/pull/21062#discussion_r569329362)
- Use default value for
TxValidationState
in the success case (https://github.com/bitcoin/bitcoin/pull/21062#discussion_r573659801).