bug#22000: Patch addressing the menu-bar frame-resize interaction

[martin rudalics]

> I have a command which cycles through the available scrollbar modes
> and sets the "next" value in default-frame-alist & applies it to all
> extant frames: However I'm aware that -mode means something specific
> in elisp and this is not that. It's not a toggle as most minor modes
> are but a 4-state (or 3-state for 3.16-).
>
> Any suggestions on a name? Or is -mode still acceptable?
> (currently called `menu-bar-scrollbar-mode' since I had
>   to call it _something_).

Here I have for example the following tri-state -mode variable:


scroll-bar-mode is a variable defined in ‘scroll-bar.el’.
Its value is ‘right’

Documentation:
Specify whether to have vertical scroll bars, and on which side.
Possible values are nil (no scroll bars), ‘left’ (scroll bars on left)
and ‘right’ (scroll bars on right).


So I see no problem in making 'menu-bar-scrollbar-mode' a multistate
variable.  Maybe one day someone wants to add a ">>" in the top right
corner to reveal further menu entries.

martin