At the moment Lily Gladstone learned she had been nominated for an Academy Award for best actress in Martin Scorsese’s drama “Killers of the Flower Moon,” the first Native American performer to do so, she was in two beloved places at once. Physically, she was on the Osage reservation in Oklahoma, where her character Mollie Burkhart had lived and where the events of the film — a true story from the 1920s — were set. “I wanted to be as close to Mollie as I could get if the good news did come,” Gladstone said, in a telephone interview a few days after the nomination announcement. “Because I owe i…