Plot synopsis: Cheech and Chong, the stoner pair who dominated the comedy scene in the 1970s and ’80s and recently reunited for their Light Up America tour, take their place in the hot seat to be roasted by close friends and fellow comedians. The duo made a name for themselves with their drug-laced humor, which kept audiences rolling in the aisles with such comedy routines as “Earache My Eye,” “Basketball Jones,