Add helpers to set the built-in pod priorities

pkg/kubemanifest/BUILD.bazel

@@ -6,6 +6,7 @@ go_library(
         "critical.go",
         "images.go",
         "manifest.go",
+        "priority.go",
         "visitor.go",
         "volumes.go",
     ],

pkg/kubemanifest/priority.go

@@ -0,0 +1,31 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package kubemanifest
+
+import (
+	v1 "k8s.io/api/core/v1"
+)
+
+// MarkPodAsNodeCritical sets the pod priority to system-node-critical
+func MarkPodAsNodeCritical(pod *v1.Pod) {
+	pod.Spec.PriorityClassName = "system-node-critical"
+}
+
+// MarkPodAsClusterCritical sets the pod priority to system-cluster-critical
+func MarkPodAsClusterCritical(pod *v1.Pod) {
+	pod.Spec.PriorityClassName = "system-cluster-critical"
+}