UCLA QB Josh Rosen could mean to the Browns what LeBron James means to the Cavs ... if he's willing to give it 100% -- so says former UCLA football coach Rick Neuheisel. Rick -- Bruins HC from 2008-2011 -- told us it's only a matter of time before the Browns find their Bron ... so why not Rosen?? "Someone's gonna be the hero of Cleveland -- look what LeBron James did for the Cavaliers. It's all possible. It's just going in there with the right attitude," Neuheisel told TMZ Sports.