You guys. Remember when Zac Efron was known for his lovely pipes and enthusiastic dance moves and not his rippling abs and ability to play a bro? It seems so long ago.But the former High School Musical star hasn't lost his skills. Efron slid behind the piano for a rousing, bluesy rendition of "Happy Birthday" in honor of Mike and Dave Need Wedding Dates co-star Adam DeVine. DeVine turned 33 on November 7, and Efron probably figured it was easier and cheaper to tickle the ivories than to buy an actual present.Alas, he didn't leap into the air or even flat-iron his hair for this performance.