User cannot delete a vmgroup if vm from that vmgroup gets deleted

[ashahi1]

Issue: User cannot delete a vmgroup if vm from that vmgroup gets deleted

Test steps:

1. Create a vmgroup and associate vm to it.
2. Delete the vm that was added to the vmgroup.
3. Try to remove vm from vmgroup - message Cannot find vm
4. Try to delete vmgroup - message Cannot delete non-empty vmgroup vmgroup1. Remove VMs from the vmgroup before deleting it.

There should be some way for user to delete a vmgroup if it's vm no longer exists. In current product behavior, there is no way for user to delete it's vmgroup if VMs from that vm group get deleted.

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Steps and their output are as follows:

1. Create a vmgroup and associate VM to it.

[root@sc-rdops-vm10-dhcp-39-239:~] /usr/lib/vmware/vmdkops/bin/vmdkops_admin.py vmgroup create --name=vmgroup1 --default-datastore=_VM_DS --vm-list=testVM-33
vmgroup 'vmgroup1' is created. Do not forget to run 'vmgroup vm add' to add vm to vmgroup.

[root@sc-rdops-vm10-dhcp-39-239:~] /usr/lib/vmware/vmdkops/bin/vmdkops_admin.py vmgroup ls
Uuid                                  Name      Description                  Default_datastore  VM_list
------------------------------------  --------  ---------------------------  -----------------  ---------
11111111-1111-1111-1111-111111111111  _DEFAULT  This is the default vmgroup  _VM_DS
baf91569-a092-44b3-b6de-18677e4091b4  vmgroup1                               _VM_DS             testVM-33

2. Deleted the vm that was added to the vmgroup.
3. Tried removing vm from vmgroup. As expected, operation fail as vm no longer exists.

[root@sc-rdops-vm10-dhcp-39-239:~] /usr/lib/vmware/vmdkops/bin/vmdkops_admin.py vmgroup vm rm --name=vmgroup1 --vm-list=testVM-33
Cannot find vm testVM-33

4. Tried removing vmgroup - could not remove vmgroup as it has vm in it even though that vm is deleted.

[root@sc-rdops-vm10-dhcp-39-239:~] /usr/lib/vmware/vmdkops/bin/vmdkops_admin.py vmgroup rm --name=vmgroup1
Cannot delete non-empty vmgroup vmgroup1. Remove VMs from the vmgroup before deleting it.
[root@sc-rdops-vm10-dhcp-39-239:~]

[govint]

Fixing via #1887