Somewhere in the universe, there’s a Venn diagram of “corny stuff” and “cool stuff,” and right in the middle of it are the best performances on America’s Best Dance Crew. For last night’s “fashion challenge” episode, West Coast B-boy group Quest Crew put on the most memorable show, with a dragged-out performance of “Bang Bang” — a cheesy concept that was saved by some serious commitment from Hok, dressed up like Ariana Grande.