When Robert Pattinson drops by “Good Morning America” Aug. 15 to promote his new indie movie “Cosmopolis,” “Twilight Saga” fans will be champing at the bit to see if he’ll also break his silence over his co-star and girlfriend Kristen Stewart’s recent cheating scandal. Speculation began burbling yesterday over whether the ABC morning show will have full access to the star or be constrained to stay away from the breakup. But sources close to ABC tell us the interview has no restrictions. “Everything’s on the table” for discussion, a source said. (Then again, remember what happened when “GMA” asked Chris Brown about Rihanna?) Two days before “GMA,” Jon Stewart will get a crack at Pattinson on “The Daily Show,” reports said yesterday. But both chats had been booked in advance for Pattinson to promote his film. When news broke of Stewart’s tryst with married “Snow White and the Huntsman” director Rupert Sanders, her gushing apology said of Pattinson, “I love him, I love him, I’m so sorry.” Pattinson’s so far remained silent.