Fix crash from Settings Search

Security Settings was returning a search indexable
resource without an xml resource (in this case id = 0).

Settings search did not handle this exception and crashed.
This patch catches the exception, and adds a TODO to fix
the indexing in security settings.

Change-Id: Ic7f05c98d99cc45fbebbdc672c7e346c27daa0f0
Fixes: 67967367
Test: robotests