Instead, never participate in the macOS system full-screen mode. There
is just too much complexity involved, and the way LibreOffice works
really isn't prepared for the concept of windows having the option
from a system point of view to being full-screenable or not.

This means that the green bubble in window title bars changes from
being a (system) full-screen toggle to being a maximize/restore
toggle. Sure, the "maximize" concept also probably can be confused
with LibreOffice's own full-screen concept.

For instance, the Start Centre window is not expecting to be made
full-screen. Still, when you from the Start Centre open a Writer
document, it is the *same* window that is re-used as the Writer
window, and then suddenly should be prepared to handle going
full-screen.

Also, it is up to each separate kind of document window whether it can
be made full-screen (from the LibreOffice point of view) or not.
Writer windows can, but Impress windows can't, for example. The
View>Full Screen menu entry is added separately each case.

Maybe I will come back to this mess later, or not. Anybody else is
welcome to have a go, too, of course.

This reverts commit 4b42fd7e.

Change-Id: I6983481cbd30c0e5190c450483b1246006c80632
Reviewed-on: https://gerrit.libreoffice.org/55049Reviewed-by: Tor Lillqvist <tml@collabora.com>
Tested-by: Tor Lillqvist <tml@collabora.com>