Once, she was a poster girl for quirky movies, good acting – and well, just being gorgeous. But when Scarlett Johansson made the move into being an actual poster girl, it was a game changer. No one complained or called her a bubble-headed capitalist when she did endorsements for Calvin Klein, L'Oréal and Louis Vuitton or Dolce & Gabbana. But when she signed on in December to be the poster girl for...