Description of problem:
When create empty reclaim policy for a storage class it should be the default one of "Delete" but not "Retain"

Version-Release number of selected component (if applicable):
openshift v3.11.0-0.16.0
kubernetes v1.11.0+d4cacc0


How reproducible:
Always

Steps to Reproduce:
1.Create a sc with "" reclaim policy
2.Create a pvc to use this sc
3.Check the pv reclaim policy

Actual results:
The pv reclaim policy is Retain


Expected results:
Should be Delete

PV Dump:
# oc get pv pvc-b593cdcd-a1f8-11e8-864b-42010af00009 -o yaml
apiVersion: v1
kind: PersistentVolume
metadata:
  annotations:
    kubernetes.io/createdby: gce-pd-dynamic-provisioner
    pv.kubernetes.io/bound-by-controller: "yes"
    pv.kubernetes.io/provisioned-by: kubernetes.io/gce-pd
  creationTimestamp: 2018-08-17T08:37:03Z
  finalizers:
  - kubernetes.io/pv-protection
  labels:
    failure-domain.beta.kubernetes.io/region: us-central1
    failure-domain.beta.kubernetes.io/zone: us-central1-a
  name: pvc-b593cdcd-a1f8-11e8-864b-42010af00009
  resourceVersion: "44316"
  selfLink: /api/v1/persistentvolumes/pvc-b593cdcd-a1f8-11e8-864b-42010af00009
  uid: b79bb9e8-a1f8-11e8-864b-42010af00009
spec:
  accessModes:
  - ReadWriteOnce
  capacity:
    storage: 1Gi
  claimRef:
    apiVersion: v1
    kind: PersistentVolumeClaim
    name: azpvc
    namespace: default
    resourceVersion: "44307"
    uid: b593cdcd-a1f8-11e8-864b-42010af00009
  gcePersistentDisk:
    fsType: ext4
    pdName: kubernetes-dynamic-pvc-b593cdcd-a1f8-11e8-864b-42010af00009
  persistentVolumeReclaimPolicy: Retain
  storageClassName: standard
  volumeMode: Filesystem
status:
  phase: Bound


PVC Dump:
# oc get pvc -o yaml
apiVersion: v1
items:
- apiVersion: v1
  kind: PersistentVolumeClaim
  metadata:
    annotations:
      pv.kubernetes.io/bind-completed: "yes"
      pv.kubernetes.io/bound-by-controller: "yes"
      volume.beta.kubernetes.io/storage-provisioner: kubernetes.io/gce-pd
    creationTimestamp: 2018-08-17T08:37:00Z
    finalizers:
    - kubernetes.io/pvc-protection
    name: azpvc
    namespace: default
    resourceVersion: "44318"
    selfLink: /api/v1/namespaces/default/persistentvolumeclaims/azpvc
    uid: b593cdcd-a1f8-11e8-864b-42010af00009
  spec:
    accessModes:
    - ReadWriteOnce
    resources:
      requests:
        storage: 1Gi
    storageClassName: standard
    volumeMode: Filesystem
    volumeName: pvc-b593cdcd-a1f8-11e8-864b-42010af00009
  status:
    accessModes:
    - ReadWriteOnce
    capacity:
      storage: 1Gi
    phase: Bound
kind: List
metadata:
  resourceVersion: ""
  selfLink: ""


StorageClass Dump (if StorageClass used by PV/PVC):
# oc get sc standard -o yaml
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  annotations:
    storageclass.beta.kubernetes.io/is-default-class: "true"
  creationTimestamp: 2018-08-17T03:26:11Z
  name: standard
  resourceVersion: "2035"
  selfLink: /apis/storage.k8s.io/v1/storageclasses/standard
  uid: 49a0b43f-a1cd-11e8-9f5e-42010af00009
parameters:
  type: pd-standard
provisioner: kubernetes.io/gce-pd
reclaimPolicy: ""
volumeBindingMode: Immediate


Additional info: