bug#44486: 27.1; C-@ chars corrupt elisp buffer

[Eli Zaretskii]

> From: Andreas Schwab <schwab@linux-m68k.org>
> Date: Fri, 06 Nov 2020 16:33:04 +0100
> Cc: 44486@debbugs.gnu.org
> 
> The null byte causes the file to be detected as binary.  You can use C-x
> C-m c to override the detection.

Right.  Or set inhibit-nul-byte-detection to a non-nil value before
reverting