Only evaluate RBAC filter for current request
Only evaluate RBAC filter for current request

The RBAC filter is retrieved from every plugin even if the current
request does not ask for the associated resource type.

If there is an exception thrown in doing that for a single plugin
it will block requests for any plugins.

Change-Id: I3efbf99b83068706f4266a02e00888b21464fb59
Closes-Bug: 1540696

openstack/searchlight,openstack/searchlight,openstack/searchlight