I would trim those two areas away rather than ponder what difference it might make. That black base plate will absorb/kill a lot of the light in there. Aint a whole heck of a lot of light in the first place. So.... yep, I would paint that flat white too.
And if the back of that screen is also black... No the factory didn't spend for white paint where raw metal serves good enough. More white paint applied by me in this case though.
