[netstack] cobalt client: log transport errors

Change-Id: Idcf649e2292fa95b89ee65368e87f36e4083b2c7
Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/405285
Reviewed-by: Tamir Duberstein <tamird@google.com>
Testability-Review: Tamir Duberstein <tamird@google.com>
Commit-Queue: Bert Muthalaly <stijlist@google.com>
diff --git a/src/connectivity/network/netstack/netstack.go b/src/connectivity/network/netstack/netstack.go
index 9a7eda8..e54bbb4 100644
--- a/src/connectivity/network/netstack/netstack.go
+++ b/src/connectivity/network/netstack/netstack.go
@@ -129,8 +129,10 @@
 			return ctx.Err()
 		case <-ticker.C:
 			events := c.Collect()
-			if status, err := cobaltLogger.LogCobaltEvents(context.Background(), events); err != nil || status != cobalt.StatusOk {
-				syslog.Warnf("cobaltLogger.LogCobaltEvents(_, %+v) = %s, %s", events, status, err)
+			if status, err := cobaltLogger.LogCobaltEvents(context.Background(), events); err != nil {
+				syslog.Warnf("cobaltLogger.LogCobaltEvents(_, %+v) failed: %s", events, err)
+			} else if status != cobalt.StatusOk {
+				syslog.Warnf("cobaltLogger.LogCobaltEvents(_, %+v) rejected: %s", events, status)
 			}
 		}
 	}