Dragon AD -- does it count as "bonus AD" for scaling?

Not sure where to put this, but I notice sometimes that the dragon AD buff doesn't work properly when it comes to bonus AD tooltip scaling. I notice this on Varus, for example. Let's say I've built him AP, so my AD is 75 + 5 (from 1 dragon), and my AP is 100 (including 1 dragon). Let's say I have 1 point in Q, 5 points in W and 2 points in E.

Q will show 10+80 to 15+128 damage (this tooltip includes both base and dragon AD) W will show 26 + 25 damage and 5 + 2% max HP per stack (this tooltip includes the full amount of AP) E shows 100 + 0 damage, clearly not including the 5 AD from dragon. (it has 60% bonus AD scaling, so should be +3)

Is this intentional? Does dragon AD not count towards "bonus AD" scaling? Or is it just not factored into the tooltip?