The nicest thing that can be said about Snitch, the film that commences Dwayne “The Rock” Johnson’s movie year, is that it’s no The Tooth Fairy. If we search for a silver lining, too, we can also rationalize that it can only be uphill from here. (And then we can cross our fingers.) Several years ago I might have opined that nobody really knew how best to utilize Johnson’s myriad talents, from his sense of humor to his obvious physicality, but even then I would have been lying; if you need to see the People’s Champion at his best, just watch The Other Guys or The Rundown and marvel at…