It is sadly not an uncommon story. Especially in the United States. “Unarmed Black Man Killed by Police.” Trayvon Martin. Eric Garner. Philandro Castile. Michael Brown. Ryan Coogler’s directorial debut, “Fruitvale Station” (2013) took an intimate look at the life and murder of one young man named Oscar Grant III. The film starts with actual cell phone footage from the train platform minutes into the new year. You see the bystanders calling out police for accosting a group of men, Grant among them. There’s a scuffle. And a bang.