Add missing ServiceAccount

Added missing ServiceAccount, ClusterRole and ClusterRoleBinding.

https://github.com/kubernetes/website/issues/15280
https://github.com/kubernetes/kubernetes/blob/master/cluster/addons/dns-horizontal-autoscaler/dns-horizontal-autoscaler.yaml

content/en/examples/admin/dns/dns-horizontal-autoscaler.yaml

@@ -1,33 +1,94 @@
+kind: ServiceAccount
+apiVersion: v1
+metadata:
+  name: kube-dns-autoscaler
+  namespace: kube-system
+  labels:
+    addonmanager.kubernetes.io/mode: Reconcile
+---
+kind: ClusterRole
+apiVersion: rbac.authorization.k8s.io/v1
+metadata:
+  name: system:kube-dns-autoscaler
+  labels:
+    addonmanager.kubernetes.io/mode: Reconcile
+rules:
+  - apiGroups: [""]
+    resources: ["nodes"]
+    verbs: ["list", "watch"]
+  - apiGroups: [""]
+    resources: ["replicationcontrollers/scale"]
+    verbs: ["get", "update"]
+  - apiGroups: ["apps"]
+    resources: ["deployments/scale", "replicasets/scale"]
+    verbs: ["get", "update"]
+# Remove the configmaps rule once below issue is fixed:
+# kubernetes-incubator/cluster-proportional-autoscaler#16
+  - apiGroups: [""]
+    resources: ["configmaps"]
+    verbs: ["get", "create"]
+---
+kind: ClusterRoleBinding
+apiVersion: rbac.authorization.k8s.io/v1
+metadata:
+  name: system:kube-dns-autoscaler
+  labels:
+    addonmanager.kubernetes.io/mode: Reconcile
+subjects:
+  - kind: ServiceAccount
+    name: kube-dns-autoscaler
+    namespace: kube-system
+roleRef:
+  kind: ClusterRole
+  name: system:kube-dns-autoscaler
+  apiGroup: rbac.authorization.k8s.io
+
+---
 apiVersion: apps/v1
 kind: Deployment
 metadata:
-  name: dns-autoscaler
+  name: kube-dns-autoscaler
   namespace: kube-system
   labels:
-    k8s-app: dns-autoscaler
+    k8s-app: kube-dns-autoscaler
+    kubernetes.io/cluster-service: "true"
+    addonmanager.kubernetes.io/mode: Reconcile
 spec:
   selector:
     matchLabels:
-      k8s-app: dns-autoscaler
+      k8s-app: kube-dns-autoscaler
   template:
     metadata:
       labels:
-        k8s-app: dns-autoscaler
+        k8s-app: kube-dns-autoscaler
     spec:
+      priorityClassName: system-cluster-critical
+      securityContext:
+        seccompProfile:
+          type: RuntimeDefault
+        supplementalGroups: [ 65534 ]
+        fsGroup: 65534
+      nodeSelector:
+        kubernetes.io/os: linux
       containers:
       - name: autoscaler
-        image: k8s.gcr.io/cluster-proportional-autoscaler-amd64:1.6.0
+        image: k8s.gcr.io/cpa/cluster-proportional-autoscaler:1.8.4
         resources:
             requests:
-            cpu: 20m
+                cpu: "20m"
-            memory: 10Mi
+                memory: "10Mi"
         command:
           - /cluster-proportional-autoscaler
           - --namespace=kube-system
-        - --configmap=dns-autoscaler
+          - --configmap=kube-dns-autoscaler
+          # Should keep target in sync with cluster/addons/dns/kube-dns.yaml.base
           - --target=<SCALE_TARGET>
           # When cluster is using large nodes(with more cores), "coresPerReplica" should dominate.
           # If using small nodes, "nodesPerReplica" should dominate.
-        - --default-params={"linear":{"coresPerReplica":256,"nodesPerReplica":16,"min":1}}
+          - --default-params={"linear":{"coresPerReplica":256,"nodesPerReplica":16,"preventSinglePointFailure":true,"includeUnschedulableNodes":true}}
           - --logtostderr=true
           - --v=2
+      tolerations:
+      - key: "CriticalAddonsOnly"
+        operator: "Exists"
+      serviceAccountName: kube-dns-autoscaler