bug#59351: 29.0.50; [PATCH] Fix mouse click position to menu bar entry

[Eli Zaretskii]

> Cc: 59351@debbugs.gnu.org
> From: Manuel Giraud <manuel@ledu-giraud.fr>
> Date: Fri, 18 Nov 2022 13:10:07 +0100
> 
> Po Lu <luangruo@yahoo.com> writes:
> 
> >> +          /* I guess this works because the menu bar is always
> >> +             at position (0, 0) in a frame.  Should this changed
> >> +             and we need a way to calculate the correct position
> >> +             into the menu bar from the position of the event in
> >> +             the frame.  */
> >
> > I think this comment is unnecessary.  Where else would a menu bar be?
> 
> I don't know.  Maybe in some distant future, menu bar will be anywhere
> :-)  It also helps with the previous comment about event position being
> relative to frame because here we are converting in f->menu_bar_window.

Why not use FRAME_TO_WINDOW_PIXEL_X and FRAME_TO_WINDOW_PIXEL_Y, and
make sure this will _always_ work?