By JUAN A. LOZANO, Associated Press HOUSTON (AP) — A black man was arrested and charged with murder in the killing of a 7-year-old black girl in a drive-by shooting that authorities said Sunday appeared to be a case of mistaken identity, not a racially motivated attack, as her family feared. Jazmine Barnes' family had described the gunman in the Dec. 30 slaying as a white man driving a red pickup and