Harvey Weinstein’s big Oscar hopeful this summer is “Fruitvale Station,” a true story about the fatal Oakland shooting of an unarmed young black man that arrived with almost miraculous timing. Hitting theaters just as the jurors in the George Zimmerman trial were deliberating. the film won the two top prizes at the Sundance Film Festival and has become a cause celebre among critics. Activists are seizing the opportunity to promote the movie, which calls for justice and implies that nothing like it has occurred yet, though the man who shot and killed Oscar Grant has already served time in prison...