webadmin: wrong quota(s) in dc-quota subtab

Caused by a call to super.syncSearch(), which created a
wrong (another) query to server.

Change-Id: I3f9f347b15633ab1e8215a45816c7aba1149252b
Bug-Url: https://bugzilla.redhat.com/950536
Signed-off-by: Gilad Chaplik <gchaplik@redhat.com>