diff --git a/core/modules/views/lib/Drupal/views/Plugin/views/PluginBase.php b/core/modules/views/lib/Drupal/views/Plugin/views/PluginBase.php
index 1f389a2..8bf057b 100644
--- a/core/modules/views/lib/Drupal/views/Plugin/views/PluginBase.php
+++ b/core/modules/views/lib/Drupal/views/Plugin/views/PluginBase.php
@@ -109,11 +109,14 @@ protected function defineOptions() { return array(); }
    *   associative array containing:
    *   - default: The default value of one option
    *   - (optional) contains: An array which describes the available options
-   *       under the key.
+   *     under the key. If contains is set, the default will be ignored and
+   *     assumed to be an empty array.
+   *   - (optional) 'translatable': TRUE if it should be translated, else FALSE.
+   *   - (optional) 'bool': TRUE if the value is boolean, else FALSE.
    */
   protected function setOptionDefaults(array &$storage, array $options) {
     foreach ($options as $option => $definition) {
-      if (isset($definition['contains']) && is_array($definition['contains'])) {
+      if (isset($definition['contains'])) {
         $storage[$option] = array();
         $this->setOptionDefaults($storage[$option], $definition['contains']);
       }