diff --git a/core/lib/Drupal/Core/Field/TypedData/FieldItemDataDefinition.php b/core/lib/Drupal/Core/Field/TypedData/FieldItemDataDefinition.php
index 7b85e8c..e8dbe48 100644
--- a/core/lib/Drupal/Core/Field/TypedData/FieldItemDataDefinition.php
+++ b/core/lib/Drupal/Core/Field/TypedData/FieldItemDataDefinition.php
@@ -43,6 +43,13 @@ public static function createFromDataType($data_type) {
   }
 
   /**
+   * Returns the field definition.
+   */
+  public function getFieldDefinition() {
+    return $this->fieldDefinition;
+  }
+
+  /**
    * Creates a new field item definition.
    *
    * @param \Drupal\Core\Field\FieldDefinitionInterface $field_definition
diff --git a/core/lib/Drupal/Core/Menu/MenuParentFormSelector.php b/core/lib/Drupal/Core/Menu/MenuParentFormSelector.php
index e57b7e8..65ac1e6 100644
--- a/core/lib/Drupal/Core/Menu/MenuParentFormSelector.php
+++ b/core/lib/Drupal/Core/Menu/MenuParentFormSelector.php
@@ -79,8 +79,8 @@ public function getParentSelectOptions($id = '', array $menus = NULL) {
   /**
    * {@inheritdoc}
    */
-  public function parentSelectElement($menu_parent, $id = '', array $menus = NULL) {
-    $options = $this->getParentSelectOptions($id, $menus);
+  public function parentSelectElement($menu_parent, $exclude_id = '', array $menus = NULL) {
+    $options = $this->getParentSelectOptions($exclude_id, $menus);
     // If no options were found, there is nothing to select.
     if ($options) {
       if (!isset($options[$menu_parent])) {
diff --git a/core/lib/Drupal/Core/Menu/MenuParentFormSelectorInterface.php b/core/lib/Drupal/Core/Menu/MenuParentFormSelectorInterface.php
index 33ada87..7e607b3 100644
--- a/core/lib/Drupal/Core/Menu/MenuParentFormSelectorInterface.php
+++ b/core/lib/Drupal/Core/Menu/MenuParentFormSelectorInterface.php
@@ -38,7 +38,7 @@ public function getParentSelectOptions($id = '', array $menus = NULL);
    * @param string $menu_parent
    *   A menu name and parent ID concatenated with a ':' character to use as the
    *   default value.
-   * @param string $id
+   * @param string $exclude_id
    *   (optional) ID of a link plugin. This will exclude the link and its
    *   children from being selected.
    * @param array $menus
@@ -51,6 +51,6 @@ public function getParentSelectOptions($id = '', array $menus = NULL);
    *   a single string containing the chosen menu name and parent ID separated
    *   by a ':' character.
    */
-  public function parentSelectElement($menu_parent, $id = '', array $menus = NULL);
+  public function parentSelectElement($menu_parent, $exclude_id = '', array $menus = NULL);
 
 }
diff --git a/core/modules/menu_link/menu_link.info.yml b/core/modules/menu_link/menu_link.info.yml
new file mode 100644
index 0000000..2c90e90
--- /dev/null
+++ b/core/modules/menu_link/menu_link.info.yml
@@ -0,0 +1,8 @@
+name: Menu link
+type: module
+description: 'Defines a menu link field type'
+package: Field types
+version: VERSION
+core: 8.x
+dependencies:
+  - field
diff --git a/core/modules/menu_link/src/Plugin/Field/FieldType/MenuLinkItem.php b/core/modules/menu_link/src/Plugin/Field/FieldType/MenuLinkItem.php
new file mode 100644
index 0000000..5fd1bb3
--- /dev/null
+++ b/core/modules/menu_link/src/Plugin/Field/FieldType/MenuLinkItem.php
@@ -0,0 +1,213 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\menu_link\Plugin\Field\FieldType\MenuLinkItem.
+ */
+
+namespace Drupal\menu_link\Plugin\Field\FieldType;
+
+use Drupal\Core\Field\FieldItemBase;
+use Drupal\Core\Field\FieldStorageDefinitionInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\TypedData\DataDefinition;
+use Drupal\Core\TypedData\DataDefinitionInterface;
+use Drupal\Core\TypedData\TypedDataInterface;
+
+/**
+ * Defines a menu link field type which stores the link, parent and menu.
+ *
+ * @FieldType(
+ *   id = "menu_link",
+ *   label = @Translation("Menu link"),
+ *   description = @Translation("Stores a title, menu and parent to insert a link to the current entity."),
+ *   default_widget = "menu_link_default"
+ * )
+ */
+class MenuLinkItem extends FieldItemBase {
+
+  /**
+   * The menu plugin manager.
+   *
+   * @var \Drupal\Core\Menu\MenuLinkManagerInterface
+   */
+  protected $menuPluginManager;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(DataDefinitionInterface $definition, $name = NULL, TypedDataInterface $parent = NULL) {
+    parent::__construct($definition, $name, $parent);
+
+    $this->menuPluginManager = \Drupal::service('plugin.manager.menu.link');
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function defaultInstanceSettings() {
+    $settings = parent::defaultInstanceSettings();
+
+    $settings['available_menus'] = array('main');
+    return $settings;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function instanceSettingsForm(array $form, FormStateInterface $form_state) {
+    $form = parent::instanceSettingsForm($form, $form_state);
+
+    $menu_options = menu_ui_get_menus();
+    $form['available_menus'] = array(
+      '#type' => 'checkboxes',
+      '#title' => $this->t('Available menus'),
+      '#default_value' => $this->getSetting('available_menus'),
+      '#options' => $menu_options,
+      '#description' => $this->t('The menus available to place links in for this content type.'),
+    );
+
+    return $form;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function propertyDefinitions(FieldStorageDefinitionInterface $field_definition) {
+    $definitions = array();
+
+    $definitions['menu_name'] = DataDefinition::create('string')
+      ->setLabel(t('Menu'));
+    $definitions['parent'] = DataDefinition::create('string')
+      ->setLabel(t('Parent menu link'));
+    $definitions['title'] = DataDefinition::create('string')
+      ->setLabel(t('Menu link title'));
+    $definitions['description'] = DataDefinition::create('string')
+      ->setLabel(t('Menu link description'));
+    $definitions['weight'] = DataDefinition::create('integer')
+      ->setLabel(t('Menu link weight'));
+
+    return $definitions;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function schema(FieldStorageDefinitionInterface $field_definition) {
+    $schema = array();
+
+    $schema['columns']['title'] = array(
+      'description' => 'The link text.',
+      'type' => 'varchar',
+      'length' => 255,
+      'not null' => FALSE,
+    );
+
+    $schema['columns']['menu_name'] = array(
+      'description' => 'The menu of the link',
+      'type' => 'varchar',
+      'length' => 255,
+      'not null' => FALSE,
+    );
+    $schema['columns']['parent'] = array(
+      'description' => 'The parent of the menu link',
+      'type' => 'varchar',
+      'length' => 255,
+      'not null' => FALSE,
+    );
+
+    $schema['columns']['weight'] = array(
+      'description' => 'The weight of the menu link',
+      'type' => 'int',
+    );
+
+    $schema['columns']['description'] = array(
+      'description' => 'The link description.',
+      'type' => 'blob',
+      'size' => 'big',
+      'not null' => FALSE,
+    );
+
+    return $schema;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function insert() {
+    parent::insert();
+
+    $this->doSave();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function update() {
+    parent::update();
+
+    $this->doSave();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function delete() {
+    parent::delete();
+
+    $plugin_id = $this->getMenuPluginId();
+    if ($this->menuPluginManager->hasDefinition($plugin_id)) {
+      $this->menuPluginManager->removeDefinition($plugin_id);
+    }
+  }
+
+  /**
+   * @TODO
+   */
+  protected function doSave() {
+    $plugin_id = $this->getMenuPluginId();
+    if (!$this->menuPluginManager->hasDefinition($plugin_id)) {
+      $this->menuPluginManager->addDefinition($plugin_id, $this->getMenuPluginDefinition());
+    }
+    else {
+     $this->menuPluginManager->updateDefinition($plugin_id, $this->getMenuPluginDefinition(), FALSE);
+    }
+  }
+
+  /**
+   * Generates the plugin ID for the associated menu link.
+   *
+   * @return string
+   */
+  protected function getMenuPluginId() {
+    $field_name = $this->definition->getFieldDefinition()->getName();
+    $entity_type_id = $this->getEntity()->getEntityTypeId();
+    return 'menu_link_field:' . "{$entity_type_id}_{$field_name}_{$this->getEntity()->uuid()}";
+  }
+
+  /**
+   * Generates the plugin definition of the associated menu link.
+   *
+   * @return array
+   */
+  protected function getMenuPluginDefinition() {
+    $menu_definition = array();
+    $menu_definition['id'] = $this->getPluginId();
+    $menu_definition['title'] = $this->values['title'];
+    $menu_definition['menu_name'] = $this->values['menu_name'];
+    $menu_definition['parent'] = $this->values['parent'];
+    $menu_definition['weight'] = $this->values['weight'];
+    $menu_definition['class'] = '\Drupal\menu_link\Plugin\Menu\MenuLinkField';
+    $menu_definition['form_class'] = '\Drupal\menu_link\Plugin\Menu\Form\MenuLinkFieldForm';
+    $menu_definition['metadata']['entity_id'] = $this->getEntity()->id();
+    $menu_definition['metadata']['entity_type_id'] = $this->getEntity()->getEntityTypeId();
+    $menu_definition['metadata']['field_name'] = $this->definition->getFieldDefinition()->getName();
+
+    $url = $this->getEntity()->urlInfo();
+    $menu_definition['route_name'] = $url->getRouteName();
+    $menu_definition['route_parameters'] = $url->getRouteParameters();
+
+    return $menu_definition;
+  }
+
+}
diff --git a/core/modules/menu_link/src/Plugin/Field/FieldWidget/MenuLinkWidget.php b/core/modules/menu_link/src/Plugin/Field/FieldWidget/MenuLinkWidget.php
new file mode 100644
index 0000000..c80985d
--- /dev/null
+++ b/core/modules/menu_link/src/Plugin/Field/FieldWidget/MenuLinkWidget.php
@@ -0,0 +1,148 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\menu_link\Plugin\Field\FieldWidget\MenuLinkWidget.
+ */
+
+namespace Drupal\menu_link\Plugin\Field\FieldWidget;
+
+use Drupal\Core\Field\FieldDefinitionInterface;
+use Drupal\Core\Field\FieldItemListInterface;
+use Drupal\Core\Field\WidgetBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Menu\MenuParentFormSelectorInterface;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\Session\AccountInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides a widget for the menu_link_item field type.
+ *
+ * @FieldWidget(
+ *   id = "menu_link_default",
+ *   label = @Translation("Menu link"),
+ *   field_types = {
+ *     "menu_link"
+ *   }
+ * )
+ */
+class MenuLinkWidget extends WidgetBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The menu parent selector.
+   *
+   * @var \Drupal\Core\Menu\MenuParentFormSelectorInterface
+   */
+  protected $menuParentSelector;
+
+  /**
+   * The current user.
+   *
+   * @var \Drupal\Core\Session\AccountInterface
+   */
+  protected $account;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct($plugin_id, $plugin_definition, FieldDefinitionInterface $field_definition, array $settings, array $third_party_settings, MenuParentFormSelectorInterface $menu_parent_selector, AccountInterface $account) {
+    parent::__construct($plugin_id, $plugin_definition, $field_definition, $settings, $third_party_settings);
+
+    $this->menuParentSelector = $menu_parent_selector;
+    $this->account = $account;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $plugin_id,
+      $plugin_definition,
+      $configuration['field_definition'],
+      $configuration['settings'],
+      $configuration['third_party_settings'],
+      $container->get('menu.parent_form_selector'),
+      $container->get('current_user')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, FormStateInterface $form_state) {
+    $default_title = isset($items[$delta]->title) ? $items[$delta]->title : NULL;
+    $default_description = isset($items[$delta]->description) ? $items[$delta]->description : NULL;
+    $default_weight = isset($items[$delta]->weight) ? $items[$delta]->weight : 0;
+
+    $available_menus = $items->getSetting('available_menus');
+    $menu = isset($items[$delta]->menu) ? $items[$delta]->menu : reset($available_menus);
+    $parent = isset($items[$delta]->parent) ? $items[$delta]->parent : "";
+    $default_menu_parent = "$menu:$parent";
+
+    if ($this->account->hasPermission('administer menu')) {
+      $element['title'] = array(
+        '#type' => 'textfield',
+        '#title' => t('Menu link title'),
+        '#default_value' => $default_title,
+      );
+
+      $element['description'] = array(
+        '#type' => 'textarea',
+        '#title' => t('Description'),
+        '#default_value' => $default_description,
+        '#rows' => 1,
+        '#description' => t('Shown when hovering over the menu link.'),
+      );
+
+      $plugin_id = $parent ? $default_menu_parent : '';
+      $parent_element = $this->menuParentSelector->parentSelectElement($default_menu_parent, $plugin_id, array_filter($available_menus));
+
+      $element['menu_parent'] = $parent_element;
+      $element['menu_parent']['#title'] = t('Parent item');
+      $element['menu_parent']['#attributes']['class'][] = 'menu-parent-select';
+
+      $element['weight'] = array(
+        '#type' => 'number',
+        '#title' => t('Weight'),
+        '#default_value' => $default_weight,
+        '#description' => t('Menu links with lower weights are displayed before links with higher weights.'),
+      );
+    }
+    else {
+      $element['title'] = array(
+        '#type' => 'value',
+        '#value' => $default_title,
+      );
+      $element['description'] = array(
+        '#type' => 'value',
+        '#value' => $default_description,
+      );
+      $element['weight'] = array(
+        '#type' => 'value',
+        '#value' => $default_weight,
+      );
+      $element['menu_parent'] = array(
+        '#type' => 'value',
+        '#value' => $default_menu_parent,
+      );
+    }
+
+    return $element;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function extractFormValues(FieldItemListInterface $items, array $form, FormStateInterface $form_state) {
+    parent::extractFormValues($items, $form, $form_state);
+
+    // Extract menu/parent from single select element.
+    foreach ($items as $delta => $item) {
+      list($item->menu_name, $item->parent) = explode(':', $item->menu_parent, 2);
+      unset($item->menu_parent);
+    }
+  }
+
+}
diff --git a/core/modules/menu_link/src/Plugin/Menu/Form/MenuLinkFieldForm.php b/core/modules/menu_link/src/Plugin/Menu/Form/MenuLinkFieldForm.php
new file mode 100644
index 0000000..8dab8d4
--- /dev/null
+++ b/core/modules/menu_link/src/Plugin/Menu/Form/MenuLinkFieldForm.php
@@ -0,0 +1,44 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\menu_link\Plugin\Menu\Form\MenuLinkFieldForm.
+ */
+
+namespace Drupal\menu_link\Plugin\Menu\Form;
+
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Menu\Form\MenuLinkDefaultForm;
+
+/**
+ * Provides the menu link edit form for the field based menu link.
+ */
+class MenuLinkFieldForm extends MenuLinkDefaultForm {
+
+  /**
+   * @var \Drupal\menu_link\Plugin\Menu\MenuLinkField
+   */
+  protected $menuLink;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
+    $form = parent::buildConfigurationForm($form, $form_state);
+
+    $entity = $this->menuLink->getEntity();
+
+    $form['info'] = array(
+      '#type' => 'item',
+      '#title' => $this->t('This link is provided by the %type: <a href="@url">@label</a>. The path cannot be edited.', array(
+        '%type' => $entity->getEntityType()->getLabel(),
+        '@url' => $entity->url(),
+        '@label' => $entity->label(),
+      )),
+    );
+
+    return $form;
+  }
+
+}
+
diff --git a/core/modules/menu_link/src/Plugin/Menu/MenuLinkField.php b/core/modules/menu_link/src/Plugin/Menu/MenuLinkField.php
new file mode 100644
index 0000000..73985dd
--- /dev/null
+++ b/core/modules/menu_link/src/Plugin/Menu/MenuLinkField.php
@@ -0,0 +1,108 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\menu_link\Plugin\Menu\MenuLinkField.
+ */
+
+namespace Drupal\menu_link\Plugin\Menu;
+
+use Drupal\Core\Entity\EntityManagerInterface;
+use Drupal\Core\Menu\MenuLinkBase;
+use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Symfony\Component\DependencyInjection\ContainerInterface;
+
+/**
+ * Provides a menu link plugin for field based menu links.
+ */
+class MenuLinkField extends MenuLinkBase implements ContainerFactoryPluginInterface {
+
+  /**
+   * The entity manager.
+   *
+   * @var \Drupal\Core\Entity\EntityManagerInterface
+   */
+  protected $entityManager;
+
+  /**
+   * Constructs a new MenuLinkField object.
+   *
+   * @param array $configuration
+   *   A configuration array containing information about the plugin instance.
+   * @param string $plugin_id
+   *   The plugin_id for the plugin instance.
+   * @param mixed $plugin_definition
+   *   The plugin implementation definition.
+   * @param \Drupal\Core\Entity\EntityManagerInterface $entity_manager
+   *   The entity manager.
+   */
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityManagerInterface $entity_manager) {
+    parent::__construct($configuration, $plugin_id, $plugin_definition);
+
+    $this->entityManager = $entity_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
+    return new static(
+      $configuration,
+      $plugin_id,
+      $plugin_definition,
+      $container->get('entity.manager')
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getTitle() {
+    return $this->pluginDefinition['title'];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getDescription() {
+    return $this->pluginDefinition['description'];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function updateLink(array $new_definition_values, $persist) {
+    $field_name = $this->getMetaData()['field_name'];
+
+    $this->pluginDefinition = $new_definition_values + $this->getPluginDefinition();
+    if ($persist) {
+      $updated = array();
+      foreach ($new_definition_values as $key => $value) {
+        $field = $this->getEntity()->{$field_name};
+        if (isset($field->{$key})) {
+          $field->{$key} = $value;
+          $updated[] = $key;
+        }
+      }
+      if ($updated) {
+        $this->getEntity()->save();
+      }
+    }
+
+    return $this->pluginDefinition;
+  }
+
+  /**
+   * Loads the entity the field was attached to.
+   *
+   * @return \Drupal\Core\Entity\EntityInterface|null
+   *   Returns the entity, if exists.
+   */
+  public function getEntity() {
+    $entity_type_id = $this->pluginDefinition['metadata']['entity_type_id'];
+    $entity_id = $this->pluginDefinition['metadata']['entity_id'];
+    $entity = $this->entityManager->getStorage($entity_type_id)->load($entity_id);
+    return $entity;
+  }
+
+}
diff --git a/core/modules/menu_ui/menu_ui.module b/core/modules/menu_ui/menu_ui.module
index 07fcb81..d45aa16 100644
--- a/core/modules/menu_ui/menu_ui.module
+++ b/core/modules/menu_ui/menu_ui.module
@@ -151,378 +151,6 @@ function menu_ui_block_view_system_menu_block_alter(array &$build, BlockPluginIn
 }
 
 /**
- * Implements hook_ENTITY_TYPE_insert() for node entities.
- */
-function menu_ui_node_insert(EntityInterface $node) {
-  menu_ui_node_save($node);
-}
-
-/**
- * Implements hook_ENTITY_TYPE_update() for node entities.
- */
-function menu_ui_node_update(EntityInterface $node) {
-  menu_ui_node_save($node);
-}
-
-/**
- * Implements hook_ENTITY_TYPE_insert() for node_type entities.
- */
-function menu_ui_node_type_insert(NodeTypeInterface $type) {
-  if ($type->isSyncing()) {
-    return;
-  }
-  \Drupal::config('menu.entity.node.' . $type->id())
-    ->set('available_menus', array('main'))
-    ->set('parent', 'main:')
-    ->save();
-}
-
-/**
- * Implements hook_ENTITY_TYPE_delete() for node_type entities.
- */
-function menu_ui_node_type_delete(NodeTypeInterface $type) {
-  if ($type->isSyncing()) {
-    return;
-  }
-  \Drupal::config('menu.entity.node.' . $type->id())->delete();
-}
-
-/**
- * Helper for hook_ENTITY_TYPE_insert() and hook_ENTITY_TYPE_update() for nodes.
- */
-function menu_ui_node_save(EntityInterface $node) {
-  if (!empty($node->menu)) {
-    /** @var \Drupal\menu_link_content\MenuLinkContentInterface $entity */
-    $definition = $node->menu;
-    if (trim($definition['title'])) {
-      if (!empty($definition['entity_id'])) {
-        $entity = entity_load('menu_link_content', $definition['entity_id']);
-        $entity->enabled->value = 1;
-        $entity->title->value = trim($definition['title']);
-        $entity->description->value = trim($definition['description']);
-        $entity->menu_name->value = $definition['menu_name'];
-        $entity->parent->value = $definition['parent'];
-        $entity->weight->value = isset($definition['weight']) ? $definition['weight'] : 0;
-      }
-      else {
-        // Create a new menu_link_content entity.
-        $entity = entity_create('menu_link_content', array(
-          'title' => trim($definition['title']),
-          'description' => trim($definition['description']),
-          'route_name' => 'entity.node.canonical',
-          'route_parameters' => array('node' => $node->id()),
-          'menu_name' => $definition['menu_name'],
-          'parent' => $definition['parent'],
-          'weight' => isset($definition['weight']) ? $definition['weight'] : 0,
-          'enabled' => 1,
-          'bundle' => 'menu_link_content',
-          'langcode' => $node->getUntranslated()->language()->id,
-        ));
-      }
-      if (!$entity->save()) {
-        drupal_set_message(t('There was an error saving the menu link.'), 'error');
-      }
-    }
-  }
-}
-
-/**
- * Implements hook_ENTITY_TYPE_predelete() for node entities.
- */
-function menu_ui_node_predelete(EntityInterface $node) {
-  // Delete all MenuLinkContent links that point to this node.
-  /** @var \Drupal\Core\Menu\MenuLinkManagerInterface $menu_link_manager */
-  $menu_link_manager = \Drupal::service('plugin.manager.menu.link');
-  $result = $menu_link_manager->loadLinksByRoute('entity.node.canonical', array('node' => $node->id()));
-
-  if (!empty($result)) {
-    foreach ($result as $id => $instance) {
-      if ($instance->isDeletable() && strpos($id, 'menu_link_content:') === 0) {
-        $instance->deleteLink();
-      }
-    }
-  }
-}
-
-/**
- * Implements hook_node_prepare_form().
- */
-function menu_ui_node_prepare_form(NodeInterface $node, $operation, FormStateInterface $form_state) {
-  if (empty($form_state['menu_link_definition'])) {
-    // Prepare the node for the edit form so that $node->menu always exists.
-    $node_type_config = \Drupal::config('menu.entity.node.' . $node->getType());
-    $menu_name = strtok($node_type_config->get('parent'), ':');
-    $definition = FALSE;
-    if ($node->id()) {
-      $id = FALSE;
-      // Give priority to the default menu
-      $type_menus = $node_type_config->get('available_menus');
-      if (in_array($menu_name, $type_menus)) {
-        $query = \Drupal::entityQuery('menu_link_content')
-          ->condition('route_name', 'entity.node.canonical')
-          ->condition('route_parameters', serialize(array('node' => $node->id())))
-          ->condition('menu_name', $menu_name)
-          ->sort('id', 'ASC')
-          ->range(0, 1);
-        $result = $query->execute();
-
-        $id = (!empty($result)) ? reset($result) : FALSE;
-      }
-      // Check all allowed menus if a link does not exist in the default menu.
-      if (!$id && !empty($type_menus)) {
-        $query = \Drupal::entityQuery('menu_link_content')
-          ->condition('route_name', 'entity.node.canonical')
-          ->condition('route_parameters', serialize(array('node' => $node->id())))
-          ->condition('menu_name', array_values($type_menus), 'IN')
-          ->sort('id', 'ASC')
-          ->range(0, 1);
-        $result = $query->execute();
-
-        $id = (!empty($result)) ? reset($result) : FALSE;
-      }
-      if ($id) {
-        $menu_link = MenuLinkContent::load($id);
-        $definition = array(
-          'entity_id' => $menu_link->id(),
-          'id' => $menu_link->getPluginId(),
-          'title' => $menu_link->getTitle(),
-          'description' => $menu_link->getDescription(),
-          'menu_name' => $menu_link->getMenuName(),
-          'parent' => $menu_link->getParentId(),
-          'weight' => $menu_link->getWeight(),
-        );
-      }
-    }
-
-    if (!$definition) {
-      $definition = array(
-        'entity_id' => 0,
-        'id' => '',
-        'title' => '',
-        'description' => '',
-        'menu_name' => $menu_name,
-        'parent' => '',
-        'weight' => 0,
-      );
-    }
-    // Set default values.
-    $form_state['menu_link_definition'] = $definition;
-  }
-}
-
-/**
- * Implements hook_form_BASE_FORM_ID_alter() for node_form.
- *
- * Adds menu item fields to the node form.
- *
- * @see menu_ui_node_submit()
- */
-function menu_ui_form_node_form_alter(&$form, FormStateInterface $form_state) {
-  // Generate a list of possible parents (not including this link or descendants).
-  // @todo This must be handled in a #process handler.
-  $node = $form_state['controller']->getEntity();
-  $definition = $form_state['menu_link_definition'];
-  $type = $node->getType();
-  /** @var \Drupal\Core\Menu\MenuParentFormSelectorInterface $menu_parent_selector */
-  $menu_parent_selector = \Drupal::service('menu.parent_form_selector');
-  $menu_names = menu_ui_get_menus();
-  $type_menus = \Drupal::config("menu.entity.node.$type")->get('available_menus');
-  $available_menus = array();
-  foreach ($type_menus as $menu) {
-    $available_menus[$menu] = $menu_names[$menu];
-  }
-  if ($definition['id']) {
-    $default = $definition['menu_name'] . ':' . $definition['parent'];
-  }
-  else {
-    $default = \Drupal::config('menu.entity.node.'.$type)->get('parent');
-  }
-  $parent_element = $menu_parent_selector->parentSelectElement($default,  $definition['id'], $available_menus);
-  // If no possible parent menu items were found, there is nothing to display.
-  if (empty($parent_element)) {
-    return;
-  }
-
-  $form['menu'] = array(
-    '#type' => 'details',
-    '#title' => t('Menu settings'),
-    '#access' => \Drupal::currentUser()->hasPermission('administer menu'),
-    '#open' => (bool) $definition['id'],
-    '#group' => 'advanced',
-    '#attached' => array(
-      'library' => array('menu/drupal.menu'),
-    ),
-    '#tree' => TRUE,
-    '#weight' => -2,
-    '#attributes' => array('class' => array('menu-link-form')),
-  );
-  $form['menu']['enabled'] = array(
-    '#type' => 'checkbox',
-    '#title' => t('Provide a menu link'),
-    '#default_value' => (int) (bool) $definition['id'],
-  );
-  $form['menu']['link'] = array(
-    '#type' => 'container',
-    '#parents' => array('menu'),
-    '#states' => array(
-      'invisible' => array(
-        'input[name="menu[enabled]"]' => array('checked' => FALSE),
-      ),
-    ),
-  );
-
-  // Populate the element with the link data.
-  foreach (array('id', 'entity_id') as $key) {
-    $form['menu']['link'][$key] = array('#type' => 'value', '#value' => $definition[$key]);
-  }
-
-  $form['menu']['link']['title'] = array(
-    '#type' => 'textfield',
-    '#title' => t('Menu link title'),
-    '#default_value' => $definition['title'],
-  );
-
-  $form['menu']['link']['description'] = array(
-    '#type' => 'textarea',
-    '#title' => t('Description'),
-    '#default_value' => $definition['description'],
-    '#rows' => 1,
-    '#description' => t('Shown when hovering over the menu link.'),
-  );
-
-  $form['menu']['link']['menu_parent'] = $parent_element;
-  $form['menu']['link']['menu_parent']['#title'] = t('Parent item');
-  $form['menu']['link']['menu_parent']['#attributes']['class'][] = 'menu-parent-select';
-
-  $form['menu']['link']['weight'] = array(
-    '#type' => 'number',
-    '#title' => t('Weight'),
-    '#default_value' => $definition['weight'],
-    '#description' => t('Menu links with lower weights are displayed before links with higher weights.'),
-  );
-}
-
-/**
- * Implements hook_node_submit().
- *
- * @see menu_ui_form_node_form_alter()
- */
-function menu_ui_node_submit(EntityInterface $node, $form, FormStateInterface $form_state) {
-  if (!$form_state->isValueEmpty('menu')) {
-    $definition = $form_state->getValue('menu');
-    if (empty($definition['enabled'])) {
-      if ($definition['entity_id']) {
-        $entity = entity_load('menu_link_content', $definition['entity_id']);
-        $entity->delete();
-      }
-    }
-    elseif (trim($definition['title']))  {
-      // Decompose the selected menu parent option into 'menu_name' and 'parent',
-      // if the form used the default parent selection widget.
-      if (!empty($definition['menu_parent'])) {
-        list($menu_name, $parent) = explode(':', $definition['menu_parent'], 2);
-        $definition['menu_name'] = $menu_name;
-        $definition['parent'] = $parent;
-      }
-      // @todo Figure out how to save this data without adding non-Field API
-      //   properties to the node entity. https://www.drupal.org/node/2310173
-      //   We have to tack this onto the node so we can save it later when we
-      //   have a node ID for any new node.
-      $node->menu = $definition;
-    }
-  }
-}
-
-/**
- * Implements hook_form_FORM_ID_alter().
- *
- * Adds menu options to the node type form.
- *
- * @see NodeTypeForm::form().
- * @see menu_ui_form_node_type_form_submit().
- */
-function menu_ui_form_node_type_form_alter(&$form, FormStateInterface $form_state) {
-  /** @var \Drupal\Core\Menu\MenuParentFormSelectorInterface $menu_parent_selector */
-  $menu_parent_selector = \Drupal::service('menu.parent_form_selector');
-  $menu_options = menu_ui_get_menus();
-  $type = $form_state['controller']->getEntity();
-  if ($type->id()) {
-    $config_values = \Drupal::config('menu.entity.node.' . $type->id())->get();
-  }
-  else {
-    $config_values = array(
-      'available_menus' => array('main'),
-      'parent' => 'main:',
-    );
-  }
-  $form['menu'] = array(
-    '#type' => 'details',
-    '#title' => t('Menu settings'),
-    '#attached' => array(
-      'library' => array('menu_ui/drupal.menu_ui.admin'),
-    ),
-    '#group' => 'additional_settings',
-  );
-  $form['menu']['menu_options'] = array(
-    '#type' => 'checkboxes',
-    '#title' => t('Available menus'),
-    '#default_value' => $config_values['available_menus'],
-    '#options' => $menu_options,
-    '#description' => t('The menus available to place links in for this content type.'),
-  );
-  // @todo See if we can avoid pre-loading all options by changing the form or
-  //   using a #process callback. https://www.drupal.org/node/2310319
-  //   To avoid an 'illegal option' error after saving the form we have to load
-  //   all available menu parents. Otherwise, it is not possible to dynamically
-  //   add options to the list using ajax.
-  $options = $menu_parent_selector->getParentSelectOptions('');
-  $form['menu']['menu_parent'] = array(
-    '#type' => 'select',
-    '#title' => t('Default parent item'),
-    '#default_value' => $config_values['parent'],
-    '#options' => $options,
-    '#description' => t('Choose the menu item to be the default parent for a new link in the content authoring form.'),
-    '#attributes' => array('class' => array('menu-title-select')),
-  );
-
-  $form['actions']['submit']['#validate'][] = 'menu_ui_form_node_type_form_validate';
-  $form['actions']['submit']['#submit'][] = 'menu_ui_form_node_type_form_submit';
-}
-
-/**
- * Submit handler for forms with menu options.
- *
- * @see menu_ui_form_node_type_form_alter().
- */
-function menu_ui_form_node_type_form_validate(&$form, FormStateInterface $form_state) {
-  $available_menus = array_filter($form_state->getValue('menu_options'));
-  // If there is at least one menu allowed, the selected item should be in
-  // one of them.
-  if (count($available_menus)) {
-    $menu_item_id_parts = explode(':', $form_state->getValue('menu_parent'));
-    if (!in_array($menu_item_id_parts[0], $available_menus)) {
-      form_set_error('menu_parent', $form_state, t('The selected menu item is not under one of the selected menus.'));
-    }
-  }
-  else {
-    $form_state->setValue('menu_parent', '');
-  }
-}
-
-/**
- * Submit handler for forms with menu options.
- *
- * @see menu_ui_form_node_type_form_alter().
- */
-function menu_ui_form_node_type_form_submit(&$form, FormStateInterface $form_state) {
-  $type = $form_state['controller']->getEntity();
-  \Drupal::config('menu.entity.node.' . $type->id())
-    ->set('available_menus', array_values(array_filter($form_state->getValue('menu_options'))))
-    ->set('parent', $form_state->getValue('menu_parent'))
-    ->save();
-}
-
-/**
  * Return an associative array of the custom menus names.
  *
  * @param $all