Merge pull request #37850 from MrHohn/gke-dns-autoscale

Automatic merge from submit-queue (batch tested with PRs 37092, 37850)

Turns on dns horizontal scaling tests for GKE

Seems like the dns-autoscaler is already enabled in [this recent gke build](https://k8s-gubernator.appspot.com/build/kubernetes-jenkins/logs/ci-kubernetes-e2e-gci-gke/769/).
Turning on the corresponding e2e tests to increase test coverage.

Probably better to wait for this fix #37261 to go in first.

@bowei @bprashanth 
cc @maisem @roberthbailey

cluster/gke/config-default.sh

@@ -41,7 +41,4 @@ ENABLE_L7_LOADBALANCING="${KUBE_ENABLE_L7_LOADBALANCING:-glbc}"
 #   standalone     - Heapster only. Metrics available via Heapster REST API.
 ENABLE_CLUSTER_MONITORING="${KUBE_ENABLE_CLUSTER_MONITORING:-standalone}"
 
-# Optional: Enable DNS horizontal autoscaler
-ENABLE_DNS_HORIZONTAL_AUTOSCALER="${KUBE_ENABLE_DNS_HORIZONTAL_AUTOSCALER:-false}"
-
 KUBE_DELETE_NETWORK=${KUBE_DELETE_NETWORK:-false}

test/e2e/dns_autoscaling.go

@@ -60,7 +60,7 @@ var _ = framework.KubeDescribe("DNS horizontal autoscaling", func() {
 	}
 
 	BeforeEach(func() {
-		framework.SkipUnlessProviderIs("gce")
+		framework.SkipUnlessProviderIs("gce", "gke")
 		c = f.ClientSet
 
 		Expect(len(framework.GetReadySchedulableNodesOrDie(c).Items)).NotTo(BeZero())