There's also this...
http://www.theonering.net/torwp/2014/11/19/94800-star-wars-trailer-attached-to-the-hobbit-the-battle-of-the-five-armies/
When Williams said he was going to start working on TFA, one of the producers at BSX Records reported that Williams was actually going to write music for the teaser (not the actual film) that is to be released with "Into the Woods." That is what he heard from people "in the know." However, it makes more sense to attach to the hobbit film. I believe companies are allowed to cross-promote a few times a year.