As he tells it, Bradley Cooper in 1999 is just another awestruck theater student in the audience of James Lipton’s interview show “Inside the Actors Studio.” Then the hunk with the laser-blue eyes seizes the chance to ask a question of Robert De Niro, his idol, his lodestar, the guy who inspired him to be an actor. De Niro tells him it’s a good one. It exceeds Cooper’s wildest dreams.