bug#22991: 25.0.92: C-u C-s does not display "Regexp I-search:" in the echo area

[Eli Zaretskii]

> From: Michael Heerdegen <michael_heerdegen@web.de>
> Cc: kaushal.modi@gmail.com,  22991@debbugs.gnu.org,  bruce.connor.am@gmail.com
> Date: Sat, 12 Mar 2016 13:51:42 +0100
> 
> If the default is different in different buffers, the user more likely
> wants to see the mode in the prompt.  So, my suggestion is to show the
> default in the prompt only when it is not the default default...

Do many users define buffer-local defaults for isearch?  IOW, will
such a logic be useful enough to justify its existence?  If yes, I
don't mind.