The two men accused of attacking a Phoenix activist and entertainer because of his sexual orientation each have pleaded guilty to a single count of aggravated assault. Jermon Barnes, 22, and Ernie Barnes, 25, will be sentenced in Maricopa County Superior Court late next month, when Judge Robert Gottsfield will weigh whether the brothers attacked Austin Head because of Head’s sexual orientation. They entered their pleas last week. Head, who was featured in a documentary about HIV-positive youths, was assaulted in November after he left a gay nightclub near Seventh Avenue and Camelback Road. Head and a friend were standing near Central Avenue and Osborn Road, about 2 1/2 miles from the club, when two men walked toward them.