Allow field collections without ids to be returned from field_collection_field_property_get()

current source tells us that this is fixed for single value fields but needs a fix in the wrapper for multiple valued ones.

Wrappers do not support multiple entity references being revisions or not yet saved entities.

did not check that though.
would be great to have.

/**
 * Entity property info getter callback for the field collection items.
 *
 * Like entity_metadata_field_property_get(), but additionally supports getting
 * not-yet saved collection items from @code $item['entity'] @endcode.
 */
function field_collection_field_property_get($entity, array $options, $name, $entity_type, $info) {
  $field = field_info_field($name);
  $langcode = field_language($entity_type, $entity, $name, isset($options['language']) ? $options['language']->language : NULL);
  $values = array();
  if (isset($entity->{$name}[$langcode])) {
    foreach ($entity->{$name}[$langcode] as $delta => $data) {
      // Wrappers do not support multiple entity references being revisions or
      // not yet saved entities. In the case of a single reference we can return
      // the entity object though.
      if ($field['cardinality'] == 1) {
        $values[$delta] = field_collection_field_get_entity($data);
      }
      elseif (isset($data['value'])) {
        $values[$delta] = $data['value'];
      }
    }
  }
  // For an empty single-valued field, we have to return NULL.
  return $field['cardinality'] == 1 ? ($values ? reset($values) : NULL) : $values;
}

patch_commit_7703becd22b5.patch queued for re-testing.

While we wait for #1587882: Allow getter callbaks to provide lists of entity objects to get committed, we could already fix the issue where metadata wrappers do not work on multi-value field collection items in hook_entity_presave

Steps to reproduce:

1. Add a multi-value field collection to an entity type
2. Create an entity of this type with values in the field collection field.
3. Create a module with a presave hook. Pseudo code:
   

   /**
    * Implements hook_entity_presave().
    */
   function mymodule_entity_presave($entity, $entity_type) {
     if ($entity_type == 'my_entity_type') {
       $wrapped = entity_metadata_wrapper($entity_type, $entity);
       dpm($wrapped->field_my_field_collection->value());
     }
   }
   

4. The dpm will output an empty array even though the field has multiple values.

Patch to implement requested functionality. Depends on #1587882: Allow getter callbaks to provide lists of entity objects.