I'd be shocked if Google doesn't get full access to use all the patents covered in the deal( assuming the reports are right and the patents are going to Lenovo), but even with that in mind a big part of the value of holding lots of patents in some technology area is (unfortunately) that you can use them as a nuclear option against someone who is suing you for some other patent to allow for MAD-style defense. IANAL but I'm not sure how they could structure a deal that gives away the patents but keeps that defensive option available.