diff --git a/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ChoiceConstraint.php b/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ChoiceConstraint.php
index d86503c..f8348b2 100644
--- a/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ChoiceConstraint.php
+++ b/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/ChoiceConstraint.php
@@ -30,7 +30,7 @@ class ChoiceConstraint extends Choice {
   public $maxMessage = 'You must select at most %limit choice.|You must select at most %limit choices.';
 
   /**
-   * Overrides Range::validatedBy().
+   * {@inheritdoc}
    */
   public function validatedBy() {
     return '\Symfony\Component\Validator\Constraints\ChoiceValidator';
diff --git a/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/LengthConstraint.php b/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/LengthConstraint.php
index 61004ef..f9bbfa9 100644
--- a/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/LengthConstraint.php
+++ b/core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/LengthConstraint.php
@@ -31,7 +31,7 @@ class LengthConstraint extends Length {
   public $exactMessage = 'This value should have exactly %limit character.|This value should have exactly %limit characters.';
 
   /**
-   * @inheritdoc
+   * Overrides Range::validatedBy().
    */
   public function validatedBy() {
     return '\Symfony\Component\Validator\Constraints\LengthValidator';
diff --git a/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListBooleanItem.php b/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListBooleanItem.php
index 0cac7df..d77cfd6 100644
--- a/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListBooleanItem.php
+++ b/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListBooleanItem.php
@@ -53,55 +53,6 @@ public static function schema(Field $field) {
   /**
    * {@inheritdoc}
    */
-  public function settingsForm(array $form, array &$form_state) {
-    $instance = $this->getInstance();
-    $field = $instance->getField();
-    $settings = $field->getFieldSettings();
-
-    $values = $settings['allowed_values'];
-    $off_value = array_shift($values);
-    $on_value = array_shift($values);
-
-    $element['allowed_values'] = array(
-      '#type' => 'value',
-      '#description' => '',
-      '#value_callback' => 'options_field_settings_form_value_boolean_allowed_values',
-      '#access' => empty($settings['allowed_values_function']),
-    );
-    $element['allowed_values']['on'] = array(
-      '#type' => 'textfield',
-      '#title' => t('On value'),
-      '#default_value' => $on_value,
-      '#required' => FALSE,
-      '#description' => t('If left empty, "1" will be used.'),
-      // Change #parents to make sure the element is not saved into field
-      // settings.
-      '#parents' => array('on'),
-    );
-    $element['allowed_values']['off'] = array(
-      '#type' => 'textfield',
-      '#title' => t('Off value'),
-      '#default_value' => $off_value,
-      '#required' => FALSE,
-      '#description' => t('If left empty, "0" will be used.'),
-      // Change #parents to make sure the element is not saved into field
-      // settings.
-      '#parents' => array('off'),
-    );
-
-    // Link the allowed value to the on / off elements to prepare for the rare
-    // case of an alter changing #parents.
-    $element['allowed_values']['#on_parents'] = &$element['allowed_values']['on']['#parents'];
-    $element['allowed_values']['#off_parents'] = &$element['allowed_values']['off']['#parents'];
-
-    $element += parent::settingsForm($form, $form_state, $element);
-
-    return $element;
-  }
-
-  /**
-   * {@inheritdoc}
-   */
   public function getPropertyDefinitions() {
     if (!isset(static::$propertyDefinitions)) {
       static::$propertyDefinitions['value'] = array(
diff --git a/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListFloatItem.php b/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListFloatItem.php
index 8b53b0f..e5f6a75 100644
--- a/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListFloatItem.php
+++ b/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListFloatItem.php
@@ -40,15 +40,15 @@ class ListFloatItem extends ListItemBase {
    * {@inheritdoc}
    */
   public static function schema(Field $field) {
-     return parent::schema($field) + array(
-       'columns' => array(
-         'value' => array(
-           'type' => 'float',
-           'not null' => FALSE,
-         ),
+    return parent::schema($field) + array(
+     'columns' => array(
+       'value' => array(
+         'type' => 'float',
+         'not null' => FALSE,
        ),
-     );
-   }
+     ),
+    );
+  }
 
   /**
    * {@inheritdoc}
diff --git a/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListIntegerItem.php b/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListIntegerItem.php
index a3c0372..dbc1d51 100644
--- a/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListIntegerItem.php
+++ b/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListIntegerItem.php
@@ -40,15 +40,15 @@ class ListIntegerItem extends ListItemBase {
    * {@inheritdoc}
    */
   public static function schema(Field $field) {
-     return parent::schema($field) + array(
-       'columns' => array(
-         'value' => array(
-           'type' => 'int',
-           'not null' => FALSE,
-         ),
+    return parent::schema($field) + array(
+     'columns' => array(
+       'value' => array(
+         'type' => 'int',
+         'not null' => FALSE,
        ),
-     );
-   }
+     ),
+    );
+  }
 
   /**
    * {@inheritdoc}
diff --git a/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListItemBase.php b/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListItemBase.php
index e5d0f5d..da35e2c 100644
--- a/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListItemBase.php
+++ b/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListItemBase.php
@@ -19,17 +19,17 @@
    * {@inheritdoc}
    */
   public static function schema(Field $field) {
-     return array(
-       'indexes' => array(
-         'value' => array('value'),
-       ),
-     );
-   }
+    return array(
+     'indexes' => array(
+       'value' => array('value'),
+     ),
+    );
+  }
 
   /**
    * {@inheritdoc}
    */
-  public function settingsForm(array $form, array &$form_state, $element = array()) {
+  public function settingsForm(array $form, array &$form_state) {
     $instance = $this->getInstance();
     $field = $instance->getField();
     $settings = $field->getFieldSettings();
@@ -60,6 +60,43 @@ public function settingsForm(array $form, array &$form_state, $element = array()
       $description .= '</p>';
       $element['allowed_values']['#description'] = $description;
     }
+    elseif ($field['type'] == 'list_boolean') {
+      $values = $settings['allowed_values'];
+      $off_value = array_shift($values);
+      $on_value = array_shift($values);
+
+      $element['allowed_values'] = array(
+        '#type' => 'value',
+        '#description' => '',
+        '#value_callback' => 'options_field_settings_form_value_boolean_allowed_values',
+        '#access' => empty($settings['allowed_values_function']),
+      );
+      $element['allowed_values']['on'] = array(
+        '#type' => 'textfield',
+        '#title' => t('On value'),
+        '#default_value' => $on_value,
+        '#required' => FALSE,
+        '#description' => t('If left empty, "1" will be used.'),
+        // Change #parents to make sure the element is not saved into field
+        // settings.
+        '#parents' => array('on'),
+      );
+      $element['allowed_values']['off'] = array(
+        '#type' => 'textfield',
+        '#title' => t('Off value'),
+        '#default_value' => $off_value,
+        '#required' => FALSE,
+        '#description' => t('If left empty, "0" will be used.'),
+        // Change #parents to make sure the element is not saved into field
+        // settings.
+        '#parents' => array('off'),
+      );
+
+      // Link the allowed value to the on / off elements to prepare for the rare
+      // case of an alter changing #parents.
+      $element['allowed_values']['#on_parents'] = &$element['allowed_values']['on']['#parents'];
+      $element['allowed_values']['#off_parents'] = &$element['allowed_values']['off']['#parents'];
+    }
 
     // Alter the description for allowed values depending on the widget type.
     if ($instance['widget']['type'] == 'options_onoff') {
diff --git a/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListTextItem.php b/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListTextItem.php
index a38ab41..0672bb6 100644
--- a/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListTextItem.php
+++ b/core/modules/options/lib/Drupal/options/Plugin/field/field_type/ListTextItem.php
@@ -40,16 +40,16 @@ class ListTextItem extends ListItemBase {
    * {@inheritdoc}
    */
   public static function schema(Field $field) {
-     return parent::schema($field) + array(
-       'columns' => array(
-         'value' => array(
-           'type' => 'varchar',
-           'length' => 255,
-           'not null' => FALSE,
-         ),
+    return parent::schema($field) + array(
+     'columns' => array(
+       'value' => array(
+         'type' => 'varchar',
+         'length' => 255,
+         'not null' => FALSE,
        ),
-     );
-   }
+     ),
+    );
+  }
 
   /**
    * {@inheritdoc}