Back in 2007, 19-year-old Armie Hammer was readying himself to become a movie star. No matter that his roles, at that point, were limited to quick one-episode stints on Veronica Mars and Desperate Housewives, and a part as “Lead Prefect” in an adaptation of My Friend Flicka. Hammer already had the height, the side part, and the old-fashioned good looks that would lead directors to compare him to the likes of Gary Cooper.He also comported himself the way people who have grown up with money often do: with confidence and charisma, or if you’re being less generous, like a little bit of an asshole. Hammer had just been cast in George Miller’s doomed DC Comics adaption Justice League: Mortal and was a perfect young Bruce Wayne, even if some in the press remained dubious. “Armie Hammer (his actual, SAG-registered name) will play Batman,” the St. Petersburg Times reported. “We guess being 6-foot-5 and having a weird name makes you qualified to play the Dark Knight.”When the movie was called off, Hammer and the other stars — including Adam Brody as The Flash, DJ Cotrona as Superman, and Megan Gale as Wonder Woman — were already deep in pre-production training. Suddenly,…