Fix ICE caused by my previous patch, that is, if super trait had more
methods tnan subtrait, compiling would fail. I simply forgot to update
variable name. Updated test case , too.
auto merge of #9527 : bmaxa/rust/master, r=alexcrichton

that is, if super trait had more methods, tnen subtrait, compiling would fail. I simply forgot to update
variable name. Updated test case , too.