webadmin: Defer item selection 'til after items are set

So far the selection was performed before the list of items was
refreshed in the view, and (presumably because of GWT implementation)
this caused the list of items to not be refreshed immediately.

Change-Id: I9ab512bc315a5f01e9ddb3fe7321b596b83e7cf3
Bug-Url: https://bugzilla.redhat.com/999882
Signed-off-by: Lior Vernia <lvernia@redhat.com>