Description of problem:

In a 3.5 cluster in 3.6 environment, pool VMs are losing permissions when restarting the ovirt-engine service.

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

Red Hat Enterprise Virtualization 3.6 with 3.5 cluster
rhevm-3.6.8.1-0.1.el6.noarch

How reproducible:
100%

Steps to Reproduce:
1. Create a 3.5 cluster in a 3.6 environment. 
2. Create a VM pool and assign permission to user.
3. Login to user portal and take a VM so that permission get assigned to a VM.
4. Restart the ovirt-engine service
5. Re-login to admin portal and check if the permission is there for the VM.

Actual results:

Permission for pool VMs are lost while restarting the engine service.

Expected results:

Permission should persist while restarting the engine service.

Additional info:

Permission are persisted after upgrading the cluster to 3.6 in my test environment.