CRM-10635 : parents processing on initial load of manage display screen of groups

This issue came due to CRM-11310 issue fix introduced :  <code>buildGroupSelector(true);</code> on load event of page in file <code>templates/CRM/Group/Form/Search.tpl </code> so that filter search can happen on page load of the manage screen.

this fix manages parent child hierarchy display as well as search filter for parents on initial page load of manage screen, so that the fix is compatible with both CRM-11310 and CRM-10635 issue.