bug#41888: 27.0.91; fix ACTION argument of display-buffer

[Eli Zaretskii]

> Cc: 41888@debbugs.gnu.org
> From: martin rudalics <rudalics@gmx.at>
> Date: Sun, 28 Jun 2020 08:37:56 +0200
> 
>  >> gud-common-init function in emacs 27 seems to have a bug in how it calls
>  >> display-buffer. The second argument passed is ACTION. According to
>  >> docstring of display-buffer, the list of functions need to be a list
>  >> within a list. The attached patch adds the missing extra pair of
>  >> parenthesis.
>  >
>  > Martin, any comments or suggestions?
> 
> I think that Richard is right and his patch will fix the problem.

Thanks, pushed to the emacs-27 branch.

Richard, in the future please accompany your changes with a
ChangeLog-style commit log message, as described in CONTRIBUTE.  (I
wrote the log message for you this time.)