If Angelina Jolie opens “Salt,” a July 23 action thriller that looks eerily like “Wanted,” her last action thriller, then we’ll have to wonder if Cruise and Diaz really have completely lost their drawing power. And if “Salt” is a disappointment, then perhaps people will cast a wider net, saying that movie stars are even more overrated than ever before, or argue that action thrillers are dead – at least until the next one that comes along has a terrific opening.