function entityreference_field_uuid_presave in Universally Unique IDentifier 7
Implements hook_field_uuid_presave().
Kept here because it is in D8 core.
Related topics
File
- ./uuid.core.inc, line 378 
- Implementation of UUID hooks for all core modules.
Code
function entityreference_field_uuid_presave($entity_type, $entity, $field, $instance, $langcode, &$items) {
  // TODO: This is not really good, but as of now 'entity_property_id_to_uuid()'
  // can't handle a single $item.
  entity_property_uuid_to_id($items, $field['settings']['target_type'], 'target_id');
}