Gru, the recovering supervillain turned huggable and lovable dad, is back in theaters. Universal premiered a new sequence from “Despicable Me 4,” the latest installment in the studio and its partner Illumination’s long-running animated franchise, at CinemaCon in Las Vegas on Wednesday. It featured an aspiring villainess (Joey King) as well as a new addition to the Gru family — Gru Jr., who...