bug#43756: Fix for TTY menus mouse interaction

[Eli Zaretskii]

> Cc: 43756@debbugs.gnu.org
> Date: Fri, 02 Oct 2020 09:45:33 -0700
> From: Jared Finder via "Bug reports for GNU Emacs,
>  the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>
> 
> * Emacs repo from git://git.sv.gnu.org/emacs.git, commit 
> f6277911eb2c520aec8f0efd80c91999226e3322
> * Run on Debian under Windows Subsystem for Linux 2 (the VM version). 
> I've also seen this on MacOS and native Win32 builds of Emacs.

Native Windows build doesn't support xterm-mouse, and the native mouse
clicks work correctly there.  If you have a recipe for the native
Windows build that shows incorrect menus popping down, please show
that.

> emacs -Q
> M-x ielm
> M-x xterm-mouse-mode

Ah, xterm-mouse-mode.  AFAIR, no one has made TTY menus work with
xterm-mouse-mode.  The first thing to do is to disable tmm-menubar,
and then you need to cause a mouse click call menu-bar-open with the
2nd argument set to the X coordinate of the click.