bug#43381: 27.1.50; Maybe wrong cursor FG color in NS port

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: alan@idiocy.org,  43381@debbugs.gnu.org,  dale@codefu.org
> Date: Thu, 17 Sep 2020 16:36:52 +0200
> 
> > Any specific suggestions for a fix?
> 
> That we do what the documentation suggests -- use the frame background
> (i.e., the default face background) as the face foreground of the
> character under point.

What if that character has a non-default foreground color?  If we
disregard it, all the characters will look the same when under the
cursor, regardless of their original face.

Besides, this is different from every other place in Emacs where we
have more than one source for face information: we always merge all
the faces.

So I cannot say I like this proposal.