DETROIT—LeBron James was ejected for drawing blood from Isaiah Stewart’s face, sending the superstar to the locker room early in the third quarter and leaving his teammates to pick up the slack. Anthony Davis and Russell Westbrook did that in a big way. Davis had 30 points, 10 rebounds and two big blocked shots late on rookie Cade Cunningham. Westbrook contributed 26 points, 10 assists and nine rebounds, leading the Los Angeles Lakers to a 121-116 comeback victory over the Detroit Pistons on Sunday night. “Everybody’s level went up when LB came out,” Davis said. The 20-year-old Cunningham, the No. 1 overall pick in the draft, had 13 points, 12 rebounds and 10 assists to become the youngest player in franchise history with a triple-double. James’ Flagrant 2 foul ended his night after his left elbow and hand appeared to make contact with Stewart’s face when they were tangled up …