Research In Motion Ltd., facing a shareholder vote on whether to split its chief executive and chairman roles, agreed to study the overhaul of its management structure to avoid a public showdown at its investors’ meeting this month.   Jim Balsillie and Mike Lazaridis are currently both co-chief executive officers and co-chairmen at the Waterloo, Ontario-based company. Betty Liu reports in today’s Movers and Shakers on Bloomberg Television's "In the Loop."