bug#47566: 28.0.50; diff-hl should use `repeat-mode' ... and not `smartrep'

[Kévin Le Gouguec]

Dmitry Gutov <dgutov@yandex.ru> writes:

> Consider adding a repeat-mode-echo option which follows what Smartrep
> does: instead of adding to the echo area, it just highlights the
> changed state in the mode line (basically a long mode lighter saying
> "========SMARTREP=======") and also colors the mode-line green.
>
> IME that works well as an indicator that we're in a "special" state.
>
> Though perhaps we could use a smaller text (like "[REPEAT]") and only
> color the text inside the brackets, rather than the whole
> mode-line. Could use some experimentation.

An entry in mode-line-modes, à la compilation-in-progress, would be
lovely IMO.