bug#9366: Display geometry change hook

[martin rudalics]

>> Maybe someone on Windows could give it a try:
>>
>> (1) With an Emacs frame run 'toggle-frame-fullscreen' (F11).
>>
>> (2) Change the resolution of the monitor the frame appears on.
>>
>> (3) Look whether the frame is still fullscreen.
>
> The frame remains full screen, both when immediately when I make the
> change and also when I choose "revert".   When I selected "revert" it
> did drop briefly out of full-screen mode but then restored itself
> properly immediately thereafter.  I have several displays and most of
> them have a full-screen emacs in them most of the time.  LMK if there
> else I could assist with.  Emacs 27.1 GNU bin dist.

Thanks.  That last sentence makes me doubt whether you really tested
this on Windows.  What is a "GNU bin dist"?  Please clarify.

martin