During the evaluation of fields to strip in responses to list
operations, pass also the first object in the list to the
policy engine.
This will avoid errors in policy evaluation if during
an upgrade from icehouse policy.json was not updated to remove
attribute-level policies dependent on resource values.
Closes-Bug: #1323715
Change-Id: Iaa6ed3bbf4a07ce0b614a4197cabdfa1cb36d427