was the special guest of the Black Eyed Peas — the freaking Black Eyed Peas — when the “I Gotta Feeling” foursome headlined the Super Bowl XLV halftime show in 2011.How will.i.am, Fergie and crew could ever relegate Usher to a backup role on the biggest stage in music is enough to make anybody go “OMG”?But 13 years after Usher swooped in and upstaged the Peas, justice was finally served when the singer had his own career moment on Sunday.This time around — midway through the showdown between the Kansas City Chiefs and the San Francisco 49ers at Allegiant Stadium in Las Vegas — it was will.i.am.