gddo-server: Let log client ping the actual context.

Change-Id: Ib7df665309e2a10d019806f83ca8ed057c42053e
Reviewed-on: https://go-review.googlesource.com/32016
Reviewed-by: Stephen Weinberg <stephenmw@google.com>
diff --git a/gddo-server/main.go b/gddo-server/main.go
index caf3452..8e69e26 100644
--- a/gddo-server/main.go
+++ b/gddo-server/main.go
@@ -1019,7 +1019,7 @@
 		}
 		logger := logc.Logger(gceLogName)
 
-		if err := logc.Ping(nil); err != nil {
+		if err := logc.Ping(ctx); err != nil {
 			log.Fatalf("Failed to ping Google Cloud Logging: %v", err)
 		}