It wasn’t Sergio Romo’s elbow that caused him to grimace on the mound and double over in apparent pain when he returned to the dugout Thursday night. Giants manager Bruce Bochy said Romo had a touch of the flu and was battling stomach cramps. That’s not a pleasant situation. But it’s a lot better than telling your All-Star closer to stick his elbow in the MRI chamber. “He felt it warming up,” Bochy said of Romo, who threw eight pitches and danced around center fielder Angel Pagan’s error in a scoreless ninth inning.