bug#40940: 27.0.91; project-query-replace-regexp stops too early

[Juri Linkov]

>> Also, using downcase is not entirely correct, we should
>> use isearch-no-upper-case-p instead.
>
> I usually like isearch-no-upper-case-p behavior, but here it doesn't fit
> the docstring, does it? There is no value of CASE-FOLD described that
> would indicate that the function will be too smart about it.
>
> So we'd need to update the docstring that the CASE-FOLD value of t will
> obey the value of `search-upper-case'. Then we'll consult it as well,
> like isearch-search does.

Recently we changed hi-lock.el to follow the same logic as
isearch-no-upper-case-p, so this will make the behavior
consistent across different packages.