bug#59778: 30.0.50; [PATCH] Fix boxed menu bar in non-toolkit X builds

[Eli Zaretskii]

> From: Manuel Giraud <manuel@ledu-giraud.fr>
> Date: Fri, 02 Dec 2022 15:03:57 +0100
> 
> This patch make the right end shadow of a boxed menu bar appear
> correctly.  It is essentially a copy/paste of what is done for the
> modeline.  I also remove it.[first|last]_visible_x settings because
> init_iterator does this job already for non DEFAULT_FACE_ID.

Thanks, this LGTM.  Could you please rebase on the current HEAD of the
master branch and resubmit?  The patch doesn't apply otherwise.