bug#53341: 29.0.50; [PATCH] Lazy highlight/count when reading query-replace string, etc.

[ndame]

>  one nice feature from that package, namely the highlighting and count of 
> matches
> as one types a regexp or string to replace

Highlighting the typed regexp in the buffer can be useful for other commands 
too,
e.g. highlight-regexp

It could be implemented in a generic way, so other commands can also use this 
facility.