Metrics auto-scaling doesn't work showing error message "cannot unmarshal array into Go value of type v1alpha1.PodMetricsList"

Issue

While testing the auto-scaling feature of openshift 3.4., the HPA can't read the performance metrics from Heapster. Showing the following error message:

[root@ocp-test ~]# oc describe hpa/helloworld
Name:                           helloworld
Namespace:                      a10
Labels:                         app=helloworld
Annotations:                    <none>
CreationTimestamp:              Mon, 06 Mar 2017 13:33:10 +0100
Reference:                      DeploymentConfig/helloworld
Target CPU utilization:         80%
Current CPU utilization:        <unset>
Min replicas:                   1
Max replicas:                   5
Events:
  FirstSeen     LastSeen        Count   From                            SubobjectPath   Type            Reason                  Message
  ---------     --------        -----   ----                            -------------   --------        ------                  -------
  33m           11s             69      {horizontal-pod-autoscaler }                    Warning         FailedGetMetrics        failed to get CPU consumption and request: failed to unmarshall heapster response: json: cannot unmarshal array into Go value of type v1alpha1.PodMetricsList
  33m           11s             69      {horizontal-pod-autoscaler }                    Warning         FailedComputeReplicas   failed to get CPU utilization: failed to get CPU consumption and request: failed to unmarshall heapster response: json: cannot unmarshal array into Go value of type v1alpha1.PodMetricsList