[Bug 54410] .NET 3.5 Checkbox checkmarks should be black instead of "Foreground" color

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=54410

--- Comment #7 from Esme Povirk  ---
I'm going to go ahead and change this, on the basis that the theme currently
uses the Foreground/Background properties in some cases and SystemColors in
other cases. Foreground and background colors should never be set together,
specifically to prevent this kind of issue.