When the Carolina Panthers beat the Seattle Seahawks in the divisional round of last year’s playoffs, Cam Newton ran around Bank of America Stadium high-fiving fans. But when a Seahawks fan dangled a “12” flag near Newton, he grabbed it, crumpled it up and tossed it while smiling. As the Seahawks prepare to host the Panthers on Sunday night, cornerback Richard Sherman was asked if Newton crossed the line with his gesture.