Version-Release number of selected component (if applicable):
3.11
4.1

Steps to Reproduce:
1. Create SS with emptyDir.sizeLimit

ss.yaml:
apiVersion: v1
kind: Service
metadata:
  name: nginx
  labels:
    app: nginx
spec:
  ports:
    - port: 80
      name: web
  clusterIP: None
  selector:
    app: nginx
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web
spec:
  serviceName: "nginx"
  replicas: 2
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
        - name: nginx
          image: k8s.gcr.io/nginx-slim:0.8
          ports:
            - containerPort: 80
              name: web
          volumeMounts:
            - name: www
              mountPath: /usr/share/nginx/html
      volumes:
        - emptyDir:
            medium: Memory
            sizeLimit: 1Mi

2. oc apply -f ss.yaml
3. oc get statefulset/web -o yaml --export | grep sizeLimit
sizeLimit is not persisted
4. when I edit from GUI I get "No changes were applied to stateful set web.Make sure any new fields you may have added are supported API fields."