Additional Study Information: This research study is designed to determine whether the study drugs are effective in treating muscle invasive bladder cancer in patients whose cancer did not stop, or whose cancer returned after being treated with other drugs, and study what kind of side effects are caused by these study drugs. To do this, a group of patients will be given MEDI4736 in combination with AZD4547, and compared with another group who will receive AZD4547 alone.