Description of problem:
There is a nasty traceback while searching for an existing hostname in Content Hosts using scoped search.

search query: "my-host-1.domain.org"
production.log:
2016-05-11 04:30:59 [app] [I] Processing by Api::V2::HostsController#index as JSON
2016-05-11 04:30:59 [app] [I]   Parameters: {"organization_id"=>"1", "page"=>"1", "search"=>"my-host-1.lab.eng.brq.redhat.com", "sort_by"=>"name", "sort_order"=>"ASC", "apiv"=>"v2"}
2016-05-11 04:30:59 [app] [W] Action failed
 | PG::Error: ERROR:  missing FROM-clause entry for table "organizations_hosts"
 | LINE 1: ...14_r9, "taxonomies"."katello_default" AS t14_r10, "organizat...

searching for non-existing hostname works fine.


Version-Release number of selected component (if applicable):
6.2.0 Beta GA10.1

How reproducible:
always

Steps to Reproduce:
1. register a host to your satellite so it appears in Content Hosts
2. Try to put its hostname to the search field and hit search
3. check production.log

Actual results:
ISE

Expected results:
Search query is being validated performed on all applicable fields.

Additional info:
Workaround is to use the explicit-field search query:
name = my-host-1.domain.org or
name ~ my-host-1.domain.org

- I'm requesting a blocker flag for this BZ as this will be hit quite often by users (single word search queries are the most commonly used)