libstd: Fix broken test.

src/libstd/future.rs

@@ -203,7 +203,7 @@ pub mod test {
     pub fn test_sendable_future() {
         let expected = ~"schlorf";
         let f = do spawn |copy expected| { copy expected };
-        do task::spawn |f, expected| {
+        do task::spawn || {
             let actual = f.get();
             assert actual == expected;
         }