text: Title: ESIPP [Slow] should handle updates to ExternalTrafficPolicy field is failing in 5k-node tests
  Body: Example failure:
  https://prow.k8s.io/view/gcs/kubernetes-jenkins/logs/ci-kubernetes-e2e-gce-scale-correctness/1248219443285200896
  
  Stacktrace:
  ```
  /go/src/k8s.io/kubernetes/_output/dockerized/go/src/k8s.io/kubernetes/test/e2e/network/service.go:3067
  Test Panicked
  /usr/local/go/src/runtime/panic.go:75
  
  Panic: runtime error: index out of range [0] with length 0
  
  Full stack:
  k8s.io/kubernetes/test/e2e/network.glob..func22.7()
  	/go/src/k8s.io/kubernetes/_output/dockerized/go/src/k8s.io/kubernetes/test/e2e/network/service.go:3117 +0x11f9
  k8s.io/kubernetes/test/e2e.RunE2ETests(0xc001f12700)
  	_output/dockerized/go/src/k8s.io/kubernetes/test/e2e/e2e.go:130 +0x324
  k8s.io/kubernetes/test/e2e.TestE2E(0xc001f12700)
  	_output/dockerized/go/src/k8s.io/kubernetes/test/e2e/e2e_test.go:119 +0x2b
  testing.tRunner(0xc001f12700, 0x4b56120)
  	/usr/local/go/src/testing/testing.go:909 +0xc9
  created by testing.(*T).Run
  	/usr/local/go/src/testing/testing.go:960 +0x350
  ```
  
  The problem seem to be related to the fact that we're running the test on private cluster (nodes doesn't have external IP address).
  
  @mm4tt @kubernetes/sig-network-bugs @kubernetes/sig-scalability-bugs 