Are Comcast’s cable business and its NBCUniversal entertainment unit on the same page when it comes to the Aereo legal battle? That’s a question worth asking in the wake of Friday’s petition by major broadcasters seeking a Supreme Court review of the case over the online TV-streaming service. As close watchers of the case will remember, Aereo’s legal defense relies in part on a precedent established several years ago in another long-running legal battle, this time between Cablevision Systems and major entertainment companies. That case was over Cablevision’s desire to offer a so-called network digital video recorder, a cloud-based service that offered Cablevision subscribers the benefits of a DVR without the need to have a DVR device in the home. Cablevision won the case and the Supreme Court in 2009 declined to hear the media companies’ appeal.