I'll believe it when I see it. These days, words are basically meaningless from these large tech companies. Actions are what matter.
at the very least, I'm not convinced this internal branch and AOSP will be close to feature parity if they do throw some stuff out.
Isn't ART Apache 2-licensed? They don't have to provide the source. I don't see why they would completely close it though. It would lead to forks, plus they have a lot of control through Google Play Services etc. already.