Another event2 evdns fix.

src/or/dns.c

@@ -1622,7 +1622,8 @@ dns_launch_correctness_checks(void)
   /* Wait a while before launching requests for test addresses, so we can
    * get the results from checking for wildcarding. */
   if (! launch_event)
-    launch_event = tor_evtimer_new(NULL, launch_test_addresses, NULL);
+    launch_event = tor_evtimer_new(tor_libevent_get_base(),
+                                   launch_test_addresses, NULL);
   timeout.tv_sec = 30;
   timeout.tv_usec = 0;
   if (evtimer_add(launch_event, &timeout)<0) {