group_type separator not set by API

The following code from CRM_Group_Form_Edit::postProcess should probably belong in CRM_Contact_BAO_Group::create instead, so that the API also behaves properly:

if ( is_array( $params['group_type'] ) )

{ $params['group_type'] = CRM_Core_DAO::VALUE_SEPARATOR . implode( CRM_Core_DAO::VALUE_SEPARATOR, array_keys( $params['group_type'] ) ) . CRM_Core_DAO::VALUE_SEPARATOR; }

else

{ $params['group_type'] = ''; }

Then, the API documentation needs to instruct developers to send group_type as an array; or even better, add code above to also parse a comma separated string.