bug#47047: 28.0.50; 'help-key-binding' face's background sub-optimal

[Stefan Kangas]

Stefan Kangas <stefan@marxist.se> writes:

> It is of course impossible to find a default background colour that will
> work with any colour.  The default was designed to work well with our
> default white background.

I tested with all our bundled themes, and the only theme in which the
default looked out of place to me was wombat.el and light-blue-theme.el.

I have updated wombat.el with a new face definition that seems more in
line with the rest of that theme.  If anyone wants to tweak it even
further, please feel free.

Unfortunately, I don't understand what style light-blue-theme.el is
trying to achieve, so I left it alone.  Perhaps Drew will have some idea
what, if anything, should be done in that case.