While leering at pretty 20-year-old Lily LaBeau as her throat is throttled by Tommy Pistol on the set of the upcoming “Taxi Driver” parody, one can’t help but think: What would Travis Bickle do? Would he shoot director General Stone in the gut and send LaBeau back home to her parents? Or, would he wait for his chance to watch the flick in some seedy theater with a date? It’s hard to know and — quite frankly — doesn’t much matter.