changes file and whitespace fix for bug5235 patch

changes/bug5235_log

@@ -0,0 +1,4 @@
+  o Minor features:
+    - Rate-limit the "Weighted bandwidth is 0.000000" message, and add
+      more information to it, so that we can track it down in case it
+      returns again. Mitigates bug 5235.

src/or/routerlist.c

@@ -1847,8 +1847,8 @@ smartlist_choose_node_by_bandwidth_weights(smartlist_t *sl,
       static ratelim_t zero_bandwidth_warning_limit =
         RATELIM_INIT(ZERO_BANDWIDTH_WARNING_INTERVAL);
       char *msg;
-      if ( ( msg = rate_limit_log( &zero_bandwidth_warning_limit,
-                                 approx_time() ) ) ) {
+      if ((msg = rate_limit_log(&zero_bandwidth_warning_limit,
+                                approx_time()))) {
         log_warn(LD_CIRC,
                  "Weighted bandwidth is %f in node selection for rule %s "
                  "(unweighted was %f) %s",