[Bug 39730] FillRect() confuses 16bit brush handles with color constants

https://bugs.winehq.org/show_bug.cgi?id=39730

--- Comment #7 from Dmitry Timoshkov  ---
(In reply to Nikolay Sivov from comment #6)
> I'm not sure what you mean, take a look at what RegisterClassEx16() does.

Thanks. Probably it would be a good idea to mention this in the first
comment, otherwise it's not clear at all what is going on.