Avoid running DNS self-tests if we're operating as a bridge

changes/bug4201

@@ -0,0 +1,5 @@
+  o Minor bugfixes:
+    - Bridges now skip DNS self-tests, to act a little more stealthily.
+      Fixes bug 4201; bugfix on 0.2.0.3-alpha, which first introduced
+      bridges. Patch by "warms0x".
+

src/or/main.c

@@ -1241,7 +1241,7 @@ run_scheduled_events(time_t now)
 
   /** 9. and if we're a server, check whether our DNS is telling stories to
    * us. */
-  if (is_server && time_to_check_for_correct_dns < now) {
+  if (public_server_mode(options) && time_to_check_for_correct_dns < now) {
     if (!time_to_check_for_correct_dns) {
       time_to_check_for_correct_dns = now + 60 + crypto_rand_int(120);
     } else {