bug#15839: 24.3.50; `isearch-allow-scroll': be able to scroll point off screen temporarily

[Juri Linkov]

> But I don't really need to understand.  I reviewed
> what you wrote about that only because you included
> it in a reply to this (other) bug report.  Ignore my
> feedback about `*-allow-shift-selection' if you like
> - no problem.

Thank you for your feedback, all your remarks were taken into consideration,
committed to master, and this enhancement request closed.