Revert "Enable run-pass/lib-run on win32. Closes rust-lang#714"

This reverts commit 1348a38.

Seems that this test is still broken on win.

src/test/run-pass/lib-run.rs

@@ -4,12 +4,19 @@ use std;
 import std::run;
 
 // Regression test for memory leaks
+// FIXME (714) Why does this fail on win32?
+
+#[cfg(target_os = "linux")]
+#[cfg(target_os = "macos")]
 fn test_leaks() {
   run::run_program("echo", []);
   run::start_program("echo", []);
   run::program_output("echo", []);
 }
 
+#[cfg(target_os = "win32")]
+fn test_leaks() {}
+
 fn main() {
   test_leaks();
 }