This was actually referenced in the Iron Man 3 movie. The kid says to Tony Stark that he could add these things in his suit to make it become stealthy, to which Tony Stark replies "You know what that's not a bad idea". However we never actally see that in the movie.
So my guess would be that the Iron Patriot armour (the only armour that wasn't destroyed in Iron Man 3) would essentially become Ultron, leading Tony Stark to make his stealth suit, as referenced in Iron Man 3.
Eh, maybe I'm wrong completely, but who knows?