bug#19889: tex-verbatim face: don't specify :family?

[Stefan Monnier <monnier@iro.umontreal.ca>]

> So presumably the problem is that it picks an x font rather than an xft one.
> See attached image for how it looks clunky in info.

Yes, that's the usual cause for blocky fonts.

> Firefox just uses "Monospace" font.

When/where?

> Gnome-terminal has "use the system fixed-with font".

How's that relevant for tex-verbatim or Info-quoted?

> IIUC, fc-match tells me that monspace == DejaVu Sans Mono.

For tex-verbatim, it shouldn't just be monospaced, but should look
somewhat like TeX's verbatim font (i.e. old typewriter style, i.e. courier).

For Info-quoted, it's not indispensable that it looks like courier, but
it should look different from the default font (by default).  IIUC the
default font nowadays is a monospaced sans-serif font, so I chose
a monospaced font with serif.

> I know little about fonts, but it seems suboptimal to me to try and
> specify a family for a handful of faces, since it's impossible to
> predict how it will look in conjunction with the user's other fonts.

I think we should define a `fixed-width-with-serif' face and inherit
from that, to make the intention clear.


        Stefan