bug#10867: 26.3; XIM preedit/status font handling

[Eli Zaretskii]

> From: Yichao Yu <yyc1992@gmail.com>
> Date: Sun, 2 Aug 2020 16:07:26 -0400
> Cc: Xuetian Weng <wengxt@gmail.com>
> 
> > ## What other programs do
> > * xterm seems to use "fixed" to lookup font
> > * qt4 
> > https://dreamswork.github.io/qt4/qximinputcontext__x11_8cpp_source.html
> > AFAICT uses different fonts?
> > * gtk I don't actually see where it set fonts...
> > @Xuetian Weng dug deeper into this
> >
> > ## Fix
> > I'm not sure what's the correct one. It seems that setting the fontSet
> > is necessary although I'm not sure how/if gtk get away with it.
> > According to @Xuetian Weng virtually no one use this setting anymore
> > so setting a dummy value to comfort xlib might be good enough? It
> > would avoid both issues at the same time.
> 
> And since it's basically a useless setting at this point, this fix seems to 
> work

Thanks.  Can someone with access to a system with this issue and
sufficient knowledge of what's going on please review this patch?
TIA