bug#4033: 23.1; list-colors-display is misleading

[Jason Rumney]

Drew Adams wrote:
> > 16-bit RGB components is what Emacs uses internally, IIRC.  That is
> > the reason we show each one as two letters.
> >     
>
> Is that right? Could you please check about this?
>   
Emacs uses 16 bit components internally, because that is what X uses in 
its APIs. I'm not aware of any graphics driver that allows more than 8 
bit granularity though, and on Windows you are restricted to 8 bit by 
the API anyway.