The alleged victim in an battery and assault case that is set to go to trial next month was found dead of natural causes Tuesday morning. But the prosecutor has opted not to drop the charges against his assailant, Thomas Leal. Don Brown’s roommate called Nevada City Police shortly after midnight Tuesday to report that he was dead, according to dispatch reports. An autopsy was performed Wednesday, and his death was ruled to be from natural causes, said Nevada County Deputy District Attorney Oliver Pong. Toxicology reports were pending. Brown’s death does not mean automatic dismissal of the case against …