Create a node startup latency tracker

Signed-off-by: Qiutong Song <songqt01@gmail.com>

cmd/kubelet/app/server.go

@@ -833,6 +833,10 @@ func run(ctx context.Context, s *options.KubeletServer, kubeDeps *kubelet.Depend
 		kubeDeps.PodStartupLatencyTracker = kubeletutil.NewPodStartupLatencyTracker()
 	}
 
+	if kubeDeps.NodeStartupLatencyTracker == nil {
+		kubeDeps.NodeStartupLatencyTracker = kubeletutil.NewNodeStartupLatencyTracker()
+	}
+
 	// TODO(vmarmol): Do this through container config.
 	oomAdjuster := kubeDeps.OOMAdjuster
 	if err := oomAdjuster.ApplyOOMScoreAdj(0, int(s.OOMScoreAdj)); err != nil {