Once again, Bella Thorne and Zendaya have the floor – the dance floor, that is, as the stars of Disney Channel’s hit series “Shake It Up” anchor Shake It Up: I <3 Dance soundtrack, a new Walt Disney Records collection of blazing dance tracks featured in the third season of the show. With performances by Bella and Zendaya, fellow Disney stars Selena Gomez , Bridgit Mendler , Roshon Fegan and Caroline Sunshine , as well as up-and-coming stars Coco Jones,…