Installation failed to set permissions

This may have been related to CRM-7627, but I also see that no permissions are created for the new 'admin' role. We should do something like the following:

$user_roles = user_roles( );
if ( $user_roles[ 3 ] = 'admin' ) {
$config =& CRM_Core_Config::singleton();

require_once 'CRM/Core/Permission.php';
$permissions =& CRM_Core_Permission::basicPermissions( );
$perms_array = array();
foreach ($permissions as $perm => $title)

{ $perms_array[] = $perm; }

user_role_grant_permissions( 3 , $perms_array );
}