Description of problem:
This bug is probably caused by the same reason for this bug:
https://bugzilla.redhat.com/show_bug.cgi?id=1406304
https://gerrit.ovirt.org/#/c/67747/

When trying to update a vm pool via API with any value, action will fail with:

<fault>
<detail>
[must be greater than or equal to 1, Attribute: vmStaticData.maxMemorySizeMb]
</detail>
<reason>Operation Failed</reason>
</fault>


Version-Release number of selected component (if applicable):
ovirt-engine-4.1.0-0.2.master.20161218144454.gitbaa2853.el7.centos.noarch

How reproducible:
Always

Steps to Reproduce:
1. Create a vm pool with size = 1.
2. Try to update the vm pool's size to 2 via api:

<vm_pool>
<size>2</size>
</vm_pool>

3. Try to update number of prestarted vms in the pool via api:

<vm_pool>
<prestarted_vms>0</prestarted_vms>
</vm_pool>

4. Try to update the description of the vm pool via api:

<vm_pool>
<description>something</description>
</vm_pool>


Actual results:
In all cases the update fails with the same error message mentioned above.

Expected results:
Update succeeds.

Additional info:
Not much information in engine.log:

2016-12-25 11:11:35,848+02 WARN  [org.ovirt.engine.core.bll.UpdateVmPoolCommand] (default task-11) [8c5437ac-d8b7-41e3-8c53-fc7e5c54b223] Validation of action 'UpdateVmPool' failed for user admin@internal-authz. Reasons: VAR__TYPE__DESKTO
P_POOL,VAR__ACTION__UPDATE,must be greater than or equal to 1,$groups [Ljava.lang.Class;@4a08d46b,$message {javax.validation.constraints.Min.message},$payload [Ljava.lang.Class;@729cab2e,$value 1,ACTION_TYPE_FAILED_ATTRIBUTE_PATH,$path vm
StaticData.maxMemorySizeMb
2016-12-25 11:11:35,874+02 ERROR [org.ovirt.engine.api.restapi.resource.AbstractBackendResource] (default task-11) [] Operation Failed: [must be greater than or equal to 1, Attribute: vmStaticData.maxMemorySizeMb]