Chromeo’s Dave 1 and P-Thugg started out as high school best friends making weird music in Montreal basements 20 years ago. They never could have guessed that their interest in electro-funk and ‘80s synths would take them to festival stages playing for thousands — and earning a Grammy nod along the way. Chromeo drops by to chat with Tom about their new album, “Adult Contemporary,” which poses the question: how do you stay funky in your 40s?