Bloomberg: Sumner Redstone is heading to trial over an ex-girlfriend’s claims he’s mentally incompetent, the result of a court ruling that may intensify competition for control of his $3 billion holdings in Viacom and CBS. A Los Angeles probate judge questioned whether it made sense for the 92-year-old media mogul to have put Viacom CEO Phillipe Dauman in charge of his health-care decisions instead of a family member.