test: fix test-process-active-wraps.js

b636ba8186 caused a regression
on Windows due to the way server handles are cleaned up. This
commit fixes the test by allowing the handle to be cleaned up.

Fixes: https://github.com/joyent/node/issues/8986
PR-URL: https://github.com/joyent/node/pull/8998
Reviewed-By: Julien Gilli <julien.gilli@joyent.com>
Reviewed-By: Bert Belder <bertbelder@gmail.com>

test/simple/test-process-active-wraps.js

@@ -65,9 +65,15 @@ var handles = [];
   });
   function onclose() {
     if (++n === handles.length) {
+      // Allow the server handle a few loop iterations to wind down.
+      // This test is highly dependent on the implementation of handle
+      // closing. If this test breaks in the future, it does not
+      // necessarily mean that Node is broken.
+      setImmediate(function() {
         setImmediate(function() {
           assert.equal(process._getActiveHandles().length, 0);
         });
+      });
     }
   }
 })();