bug#39908: 26.2; flush-lines and keep-lines should say how many lines were flushed

[Noam Postavsky]

ndame <emacsuser@freemail.hu> writes:

> report the number of deletions performed which can be useful info.
>
> This is easy to do by incrementing a counter at the two delete-region calls
> in keep-lines.

No, you are mistaken.  For keep-lines, the number of deletions is equal
to the number of kept lines.  Only for flush-lines the number of
deletions is the same as the number of deleted lines (in both cases,
assuming all matches are on single lines).