diff --git a/core/modules/edit/lib/Drupal/edit/Form/EditFieldForm.php b/core/modules/edit/lib/Drupal/edit/Form/EditFieldForm.php
index 35f8b2f..916c3df 100644
--- a/core/modules/edit/lib/Drupal/edit/Form/EditFieldForm.php
+++ b/core/modules/edit/lib/Drupal/edit/Form/EditFieldForm.php
@@ -177,18 +177,18 @@ protected function buildEntity(array $form, array &$form_state) {
     $entity = clone $form_state['entity'];
 
     $field_name = $form_state['field_name'];
-    $field = $entity->getNGEntity()->get($field_name);
-    if ($field->getFieldDefinition() instanceof FieldInstanceInterface) {
+    $items = $entity->get($field_name);
+    if ($items->getFieldDefinition() instanceof FieldInstanceInterface) {
       field_attach_extract_form_values($entity, $form, $form_state, array('field_name' => $field_name));
     }
     else {
-      \Drupal::service('plugin.manager.field.widget')->baseFieldExtractFormValues($field, $form, $form_state, $form_state['langcode']);
+      \Drupal::service('plugin.manager.field.widget')->baseFieldExtractFormValues($items, $form, $form_state);
     }
 
     // @todo Refine automated log messages and abstract them to all entity
     //   types: http://drupal.org/node/1678002.
     if ($entity->entityType() == 'node' && $entity->isNewRevision() && !isset($entity->log)) {
-      $entity->log = t('Updated the %field-name field through in-place editing.', array('%field-name' => $field->getFieldDefinition()->getFieldLabel()));
+      $entity->log = t('Updated the %field-name field through in-place editing.', array('%field-name' => $items->getFieldDefinition()->getFieldLabel()));
     }
 
     return $entity;
diff --git a/core/modules/field/lib/Drupal/field/Plugin/Type/Widget/WidgetPluginManager.php b/core/modules/field/lib/Drupal/field/Plugin/Type/Widget/WidgetPluginManager.php
index 5e4bb6b..c614133 100644
--- a/core/modules/field/lib/Drupal/field/Plugin/Type/Widget/WidgetPluginManager.php
+++ b/core/modules/field/lib/Drupal/field/Plugin/Type/Widget/WidgetPluginManager.php
@@ -11,6 +11,7 @@
 use Drupal\Component\Plugin\PluginManagerBase;
 use Drupal\Component\Plugin\Discovery\ProcessDecorator;
 use Drupal\Core\Cache\CacheBackendInterface;
+use Drupal\Core\Entity\Field\FieldItemListInterface;
 use Drupal\Core\Entity\Field\FieldTypePluginManager;
 use Drupal\Core\Extension\ModuleHandlerInterface;
 use Drupal\Core\Language\LanguageManager;
@@ -214,7 +215,7 @@ public function getDefaultSettings($type) {
   /**
    * @todo Document.
    */
-  public function baseFieldForm(FieldInterface $field, array &$form, array &$form_state, $langcode) {
+  public function baseFieldForm(FieldItemListInterface $field, array &$form, array &$form_state) {
     $options = array(
       'field_definition' => $field->getFieldDefinition(),
       'form_mode' => 'default',
@@ -225,18 +226,16 @@ public function baseFieldForm(FieldInterface $field, array &$form, array &$form_
     }
     $widget = $this->getInstance($options);
 
-    $entity = $field->getParent()->getBCEntity();
-
     $form += array('#parents' => array());
-    $result = $widget->form($entity, $langcode, $field, $form, $form_state);
-    $field_name = $field->getName();
+    $result = $widget->form($field, $form, $form_state);
+    $field_name = $field->getFieldDefinition()->getFieldName();
     return isset($result[$field_name]) ? $result[$field_name] : array();
   }
 
   /**
    * @todo Document.
    */
-  public function baseFieldExtractFormValues(FieldInterface $field, array &$form, array &$form_state, $langcode) {
+  public function baseFieldExtractFormValues(FieldItemListInterfaceInterface $field, array &$form, array &$form_state) {
     $options = array(
       'field_definition' => $field->getFieldDefinition(),
       'form_mode' => 'default',
@@ -247,9 +246,7 @@ public function baseFieldExtractFormValues(FieldInterface $field, array &$form,
     }
     $widget = $this->getInstance($options);
 
-    $entity = $field->getParent()->getBCEntity();
-
-    $widget->extractFormValues($entity, $langcode, $field, $form, $form_state);
+    $widget->extractFormValues($field, $form, $form_state);
   }
 
 }
diff --git a/core/modules/node/lib/Drupal/node/NodeFormController.php b/core/modules/node/lib/Drupal/node/NodeFormController.php
index cb7516e..a82af35 100644
--- a/core/modules/node/lib/Drupal/node/NodeFormController.php
+++ b/core/modules/node/lib/Drupal/node/NodeFormController.php
@@ -447,7 +447,7 @@ public function buildEntity(array $form, array &$form_state) {
     else {
       $node->setCreatedTime(REQUEST_TIME);
     }
-    \Drupal::service('plugin.manager.field.widget')->baseFieldExtractFormValues($node->title, $form, $form_state, $this->getFormLangcode($form_state));
+    \Drupal::service('plugin.manager.field.widget')->baseFieldExtractFormValues($node->title, $form, $form_state);
     return $node;
   }
 
diff --git a/core/modules/node/lib/Drupal/node/Plugin/field/widget/TitleWidget.php b/core/modules/node/lib/Drupal/node/Plugin/field/widget/TitleWidget.php
index cd4702a..43cfd81 100644
--- a/core/modules/node/lib/Drupal/node/Plugin/field/widget/TitleWidget.php
+++ b/core/modules/node/lib/Drupal/node/Plugin/field/widget/TitleWidget.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\node\Plugin\field\widget;
 
+use Drupal\Core\Entity\Field\FieldItemListInterface;
 use Drupal\field\Annotation\FieldWidget;
 use Drupal\Component\Utility\NestedArray;
 use Drupal\Core\Annotation\Translation;
@@ -31,9 +32,11 @@ class TitleWidget extends WidgetBase {
   /**
    * {@inheritdoc}
    */
-  public function form(EntityInterface $entity, $langcode, FieldInterface $items, array &$form, array &$form_state, $get_delta = NULL) {
+  public function form(FieldItemListInterface $items, array &$form, array &$form_state, $get_delta = NULL) {
     $field_name = $this->fieldDefinition->getFieldName();
 
+    $entity = $items->getEntity();
+
     // @todo Make EntityManager::getFieldDefinitions() allow for per-bundle
     //   definitions of base fields, so that here, we could just call
     //   $this->fieldDefinition->getFieldLabel() instead.
@@ -58,7 +61,7 @@ public function form(EntityInterface $entity, $langcode, FieldInterface $items,
   /**
    * {@inheritdoc}
    */
-  public function extractFormValues(EntityInterface $entity, $langcode, FieldInterface $items, array $form, array &$form_state) {
+  public function extractFormValues(FieldItemListInterface $items, array $form, array &$form_state) {
     $field_name = $this->fieldDefinition->getFieldName();
 
     // Extract the values from $form_state['values'].
@@ -74,7 +77,7 @@ public function extractFormValues(EntityInterface $entity, $langcode, FieldInter
   /**
    * {@inheritdoc}
    */
-  public function formElement(FieldInterface $items, $delta, array $element, $langcode, array &$form, array &$form_state) {
+  public function formElement(FieldItemListInterface $items, $delta, array $element, array &$form, array &$form_state) {
     return array();
   }
 }