[RFC 2/2] Share user32 combo with comctl32 combo

[Gabriel Ivăncescu]

On Sat, Nov 10, 2018 at 7:06 PM Fabian Maurer <dark.shadow4 at web.de> wrote:
>
> Currently combobox (and other controls) are duplicated in
> user32 and comctl32.
> Since most of the code is the same,
> it would make sense to deduplicate it, and have one common
> implementation to for both versions of the control.
>
> This is a POC implementation on how I imagine it could be done,
> is this something we could implement?

I'd personally love having to not change them both every time, so for
what it's worth, this idea is very worth pursuing in my opinion, but I
don't think that #including a .c file makes any sense.

Should probably be a header at least, but idk if it's acceptable to
put that under include.