This should make us less likely to fail in the gate because of listing
consistency issues.
Drive-by: Remove the allowed_headers override; that hasn't been necessary
since we updated the default value a while back.
Change-Id: Id280bc93ed6e899a62b0115fdf144a564ef0cd8d
Related-Change: Ib82e175096716e42aecdab48f01f079e09da6a1d