To hear Peter Roth tell it, friends, including J.J. Abrams, had been insisting he needed to know Ava DuVernay long before their first meeting. So when the longtime Warner Bros. TV executive found himself across from the filmmaker at the Los Angeles offices of Oprah Winfrey’s cable network, OWN, to discuss collaborating on DuVernay’s Louisiana-set television drama “Queen Sugar,” the creative connection, as they say, was instant.