Fix rt-sched-1.rs (broke in 6fc730b)

Author: bblum

src/test/run-pass/rt-sched-1.rs

@@ -1,13 +1,15 @@
 // Tests of the runtime's scheduler interface
 
+import ptr::is_null;
+
 type sched_id = int;
-type task_id = int;
+type task_id = *libc::c_void;
 
 type task = *libc::c_void;
 type closure = *libc::c_void;
 
 native mod rustrt {
-    fn rust_new_sched(num_threads: uint) -> sched_id;
+    fn rust_new_sched(num_threads: libc::uintptr_t) -> sched_id;
     fn rust_get_sched_id() -> sched_id;
     fn rust_new_task_in_sched(id: sched_id) -> task_id;
     fn start_task(id: task_id, f: closure);