CRM-15732 : fix looking up deleted 'On behalf' orgs

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* CRM-15732: Donations with an On Behalf Of an organization profile dedupes with contacts in the trash
  https://issues.civicrm.org/jira/browse/CRM-15732
Merge pull request #4781 from civicrm/CRM-15732

CRM-15732 : fix looking up deleted 'On behalf' orgs