diff --git a/core/modules/comment/comment.admin.inc b/core/modules/comment/comment.admin.inc
index 99bb6b0..8f618e5 100644
--- a/core/modules/comment/comment.admin.inc
+++ b/core/modules/comment/comment.admin.inc
@@ -5,8 +5,6 @@
  * Admin page callbacks for the Comment module.
  */
 
-use Drupal\comment\CommentInterface;
-
 /**
  * Page callback: Presents an administrative comment listing.
  *
@@ -72,7 +70,7 @@ function comment_admin_overview($form, &$form_state, $arg) {
   );
 
   // Load the comments that need to be displayed.
-  $status = ($arg == 'approval') ? CommentInterface::NOT_PUBLISHED : CommentInterface::PUBLISHED;
+  $status = ($arg == 'approval') ? COMMENT_NOT_PUBLISHED : COMMENT_PUBLISHED;
   $header = array(
     'subject' => array('data' => t('Subject'), 'field' => 'subject'),
     'author' => array('data' => t('Author'), 'field' => 'name', 'class' => array(RESPONSIVE_PRIORITY_MEDIUM)),
@@ -220,10 +218,10 @@ function comment_admin_overview_submit($form, &$form_state) {
       $comment = comment_load($value);
 
       if ($operation == 'unpublish') {
-        $comment->status->value = CommentInterface::NOT_PUBLISHED;
+        $comment->status->value = COMMENT_NOT_PUBLISHED;
       }
       elseif ($operation == 'publish') {
-        $comment->status->value = CommentInterface::PUBLISHED;
+        $comment->status->value = COMMENT_PUBLISHED;
       }
       $comment->save();
     }
diff --git a/core/modules/comment/comment.module b/core/modules/comment/comment.module
index 145690b..8debaef 100644
--- a/core/modules/comment/comment.module
+++ b/core/modules/comment/comment.module
@@ -20,6 +20,16 @@
 use Drupal\file\FileInterface;
 
 /**
+ * Comment is awaiting approval.
+ */
+const COMMENT_NOT_PUBLISHED = 0;
+
+/**
+ * Comment is published.
+ */
+const COMMENT_PUBLISHED = 1;
+
+/**
  * Comments are displayed in a flat list - expanded.
  */
 const COMMENT_MODE_FLAT = 0;
@@ -222,7 +232,7 @@ function comment_menu_alter(&$items) {
  */
 function comment_count_unpublished() {
   $count = db_query('SELECT COUNT(cid) FROM {comment} WHERE status = :status', array(
-    ':status' => CommentInterface::NOT_PUBLISHED,
+    ':status' => COMMENT_NOT_PUBLISHED,
   ))->fetchField();
   return t('Unapproved comments (@count)', array('@count' => $count));
 }
@@ -318,7 +328,7 @@ function comment_get_recent($number = 10) {
   $query = db_select('comment', 'c');
   $query->addMetaData('base_table', 'comment');
   $query->fields('c')
-    ->condition('c.status', CommentInterface::PUBLISHED);
+    ->condition('c.status', COMMENT_PUBLISHED);
   if (\Drupal::moduleHandler()->moduleExists('node')) {
     // Special case to filter by published content.
     $query->innerJoin('node_field_data', 'n', "n.nid = c.entity_id AND c.entity_type = 'node'");
@@ -381,7 +391,7 @@ function comment_new_page_count($num_comments, $new_replies, EntityInterface $en
       ->condition('entity_id', $entity->id())
       ->condition('entity_type', $entity->entityType())
       ->condition('field_id', $entity->entityType() . '__' . $field_name)
-      ->condition('status', CommentInterface::PUBLISHED)
+      ->condition('status', COMMENT_PUBLISHED)
       ->orderBy('created', 'DESC')
       ->orderBy('cid', 'DESC')
       ->range(0, $new_replies);
@@ -402,7 +412,7 @@ function comment_new_page_count($num_comments, $new_replies, EntityInterface $en
                       AND entity_type = :entity_type
                       AND field_id = :field_id
                       AND status = :status AND SUBSTRING(thread, 1, (LENGTH(thread) - 1)) < :thread', array(
-      ':status' => CommentInterface::PUBLISHED,
+      ':status' => COMMENT_PUBLISHED,
       ':entity_id' => $entity->id(),
       ':field_id' => $entity->entityType() . '__' . $field_name,
       ':entity_type' => $entity->entityType(),
@@ -712,8 +722,8 @@ function comment_get_thread(EntityInterface $entity, $field_name, $mode, $commen
     ->addMetaData('field_name', $field_name);
 
   if (!user_access('administer comments')) {
-    $query->condition('c.status', CommentInterface::PUBLISHED);
-    $count_query->condition('c.status', CommentInterface::PUBLISHED);
+    $query->condition('c.status', COMMENT_PUBLISHED);
+    $count_query->condition('c.status', COMMENT_PUBLISHED);
   }
   if ($mode == COMMENT_MODE_FLAT) {
     $query->orderBy('c.cid', 'ASC');
@@ -1185,7 +1195,7 @@ function comment_num_new($entity_id, $entity_type, $field_name = NULL, $timestam
     $query->addExpression('COUNT(cid)');
     $query->condition('c.entity_type', $entity_type)
       ->condition('c.entity_id', $entity_id)
-      ->condition('c.status', CommentInterface::PUBLISHED)
+      ->condition('c.status', COMMENT_PUBLISHED)
       ->condition('c.created', $timestamp, '>');
     if ($field_name) {
       // Limit to a particular field.
@@ -1226,7 +1236,7 @@ function comment_get_display_ordinal($cid, $instance) {
   $query->addExpression('COUNT(*)', 'count');
   $query->condition('c2.cid', $cid);
   if (!user_access('administer comments')) {
-    $query->condition('c1.status', CommentInterface::PUBLISHED);
+    $query->condition('c1.status', COMMENT_PUBLISHED);
   }
 
   if ($instance->getSetting('default_mode') == COMMENT_MODE_FLAT) {
@@ -1303,7 +1313,7 @@ function comment_preview(CommentInterface $comment, array &$form_state) {
   if ($comment->pid->target_id) {
     $build = array();
     $parent = $comment->pid->entity;
-    if ($parent && $parent->status->value == CommentInterface::PUBLISHED) {
+    if ($parent && $parent->status->value == COMMENT_PUBLISHED) {
       $build = comment_view($parent);
     }
   }
@@ -1468,7 +1478,7 @@ function template_preprocess_comment(&$variables) {
     $variables['status'] = 'preview';
   }
   else {
-    $variables['status'] = ($comment->status->value == CommentInterface::NOT_PUBLISHED) ? 'unpublished' : 'published';
+    $variables['status'] = ($comment->status->value == COMMENT_NOT_PUBLISHED) ? 'unpublished' : 'published';
   }
 
   // Gather comment classes.
@@ -1649,7 +1659,7 @@ function comment_ranking() {
  */
 function comment_file_download_access($field, EntityInterface $entity, FileInterface $file) {
   if ($entity->entityType() == 'comment') {
-    if (user_access('access comments') && $entity->status->value == CommentInterface::PUBLISHED || user_access('administer comments')) {
+    if (user_access('access comments') && $entity->status->value == COMMENT_PUBLISHED || user_access('administer comments')) {
       $commented_entity = entity_load($entity->entity_type->value, $entity->entity_id->value);
       // Check access to parent entity.
       return $commented_entity->access('view');
diff --git a/core/modules/comment/lib/Drupal/comment/CommentAccessController.php b/core/modules/comment/lib/Drupal/comment/CommentAccessController.php
index ce25a1c..800991f 100644
--- a/core/modules/comment/lib/Drupal/comment/CommentAccessController.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentAccessController.php
@@ -28,7 +28,7 @@ protected function checkAccess(EntityInterface $entity, $operation, $langcode, A
         break;
 
       case 'update':
-        return ($account->id() && $account->id() == $entity->uid->value && $entity->status->value == CommentInterface::PUBLISHED && user_access('edit own comments', $account)) || user_access('administer comments', $account);
+        return ($account->id() && $account->id() == $entity->uid->value && $entity->status->value == COMMENT_PUBLISHED && user_access('edit own comments', $account)) || user_access('administer comments', $account);
         break;
 
       case 'delete':
diff --git a/core/modules/comment/lib/Drupal/comment/CommentFormController.php b/core/modules/comment/lib/Drupal/comment/CommentFormController.php
index 8a5d52f..d0066a8 100644
--- a/core/modules/comment/lib/Drupal/comment/CommentFormController.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentFormController.php
@@ -117,7 +117,7 @@ public function form(array $form, array &$form_state) {
     // Prepare default values for form elements.
     if ($is_admin) {
       $author = $comment->name->value;
-      $status = (isset($comment->status->value) ? $comment->status->value : CommentInterface::NOT_PUBLISHED);
+      $status = (isset($comment->status->value) ? $comment->status->value : COMMENT_NOT_PUBLISHED);
       if (empty($form_state['comment_preview'])) {
         $form['#title'] = $this->t('Edit comment %title', array(
           '%title' => $comment->subject->value,
@@ -131,7 +131,7 @@ public function form(array $form, array &$form_state) {
       else {
         $author = ($comment->name->value ? $comment->name->value : '');
       }
-      $status = ($this->currentUser->hasPermission('skip comment approval') ? CommentInterface::PUBLISHED : CommentInterface::NOT_PUBLISHED);
+      $status = ($this->currentUser->hasPermission('skip comment approval') ? COMMENT_PUBLISHED : COMMENT_NOT_PUBLISHED);
     }
 
     $date = '';
@@ -195,8 +195,8 @@ public function form(array $form, array &$form_state) {
       '#title' => $this->t('Status'),
       '#default_value' => $status,
       '#options' => array(
-        CommentInterface::PUBLISHED => $this->t('Published'),
-        CommentInterface::NOT_PUBLISHED => $this->t('Not published'),
+        COMMENT_PUBLISHED => $this->t('Published'),
+        COMMENT_NOT_PUBLISHED => $this->t('Not published'),
       ),
       '#access' => $is_admin,
     );
@@ -383,7 +383,7 @@ public function save(array $form, array &$form_state) {
       watchdog('content', 'Comment posted: %subject.', array('%subject' => $comment->subject->value), WATCHDOG_NOTICE, l(t('view'), 'comment/' . $comment->id(), array('fragment' => 'comment-' . $comment->id())));
 
       // Explain the approval queue if necessary.
-      if ($comment->status->value == CommentInterface::NOT_PUBLISHED) {
+      if ($comment->status->value == COMMENT_NOT_PUBLISHED) {
         if (!$this->currentUser->hasPermission('administer comments')) {
           drupal_set_message($this->t('Your comment has been queued for review by site administrators and will be published after approval.'));
         }
diff --git a/core/modules/comment/lib/Drupal/comment/CommentInterface.php b/core/modules/comment/lib/Drupal/comment/CommentInterface.php
index 28ec9fb..fe7f40d 100644
--- a/core/modules/comment/lib/Drupal/comment/CommentInterface.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentInterface.php
@@ -16,16 +16,6 @@
 interface CommentInterface extends ContentEntityInterface, EntityChangedInterface {
 
   /**
-   * Comment is awaiting approval.
-   */
-  const NOT_PUBLISHED = 0;
-
-  /**
-   * Comment is published.
-   */
-  const PUBLISHED = 1;
-
-  /**
    * Returns the permalink URL for this comment.
    *
    * @return array
diff --git a/core/modules/comment/lib/Drupal/comment/CommentStorageController.php b/core/modules/comment/lib/Drupal/comment/CommentStorageController.php
index e23af78..0d93c65 100644
--- a/core/modules/comment/lib/Drupal/comment/CommentStorageController.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentStorageController.php
@@ -62,7 +62,7 @@ public function updateEntityStatistics(CommentInterface $comment) {
     $count = $query->condition('c.entity_id', $comment->entity_id->value)
       ->condition('c.entity_type', $comment->entity_type->value)
       ->condition('c.field_id', $comment->field_id->value)
-      ->condition('c.status', CommentInterface::PUBLISHED)
+      ->condition('c.status', COMMENT_PUBLISHED)
       ->execute()
       ->fetchField();
 
@@ -73,7 +73,7 @@ public function updateEntityStatistics(CommentInterface $comment) {
         ->condition('c.entity_id', $comment->entity_id->value)
         ->condition('c.entity_type', $comment->entity_type->value)
         ->condition('c.field_id', $comment->field_id->value)
-        ->condition('c.status', CommentInterface::PUBLISHED)
+        ->condition('c.status', COMMENT_PUBLISHED)
         ->orderBy('c.created', 'DESC')
         ->range(0, 1)
         ->execute()
diff --git a/core/modules/comment/lib/Drupal/comment/CommentStorageControllerInterface.php b/core/modules/comment/lib/Drupal/comment/CommentStorageControllerInterface.php
index 4583f20..69ba909 100644
--- a/core/modules/comment/lib/Drupal/comment/CommentStorageControllerInterface.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentStorageControllerInterface.php
@@ -9,6 +9,7 @@
 
 use Drupal\Core\Entity\EntityInterface;
 use Drupal\Core\Entity\EntityStorageControllerInterface;
+use Drupal\comment\CommentInterface;
 
 /**
  * Defines a common interface for comment entity controller classes.
diff --git a/core/modules/comment/lib/Drupal/comment/CommentViewBuilder.php b/core/modules/comment/lib/Drupal/comment/CommentViewBuilder.php
index dc4cd61..be9c41f 100644
--- a/core/modules/comment/lib/Drupal/comment/CommentViewBuilder.php
+++ b/core/modules/comment/lib/Drupal/comment/CommentViewBuilder.php
@@ -231,7 +231,7 @@ protected static function buildLinks(CommentInterface $entity, EntityInterface $
           'html' => TRUE,
         );
       }
-      if ($entity->status->value == CommentInterface::NOT_PUBLISHED && $entity->access('approve')) {
+      if ($entity->status->value == COMMENT_NOT_PUBLISHED && $entity->access('approve')) {
         $links['comment-approve'] = array(
           'title' => t('Approve'),
           'route_name' => 'comment.approve',
diff --git a/core/modules/comment/lib/Drupal/comment/Controller/CommentController.php b/core/modules/comment/lib/Drupal/comment/Controller/CommentController.php
index b1b127f..ccb3a4a 100644
--- a/core/modules/comment/lib/Drupal/comment/Controller/CommentController.php
+++ b/core/modules/comment/lib/Drupal/comment/Controller/CommentController.php
@@ -97,7 +97,7 @@ public static function create(ContainerInterface $container) {
    * @return \Symfony\Component\HttpFoundation\RedirectResponse.
    */
   public function commentApprove(CommentInterface $comment) {
-    $comment->status->value = CommentInterface::PUBLISHED;
+    $comment->status->value = COMMENT_PUBLISHED;
     $comment->save();
 
     drupal_set_message($this->t('Comment approved.'));
@@ -246,7 +246,7 @@ public function getReplyForm(Request $request, $entity_type, $entity_id, $field_
         // Load the parent comment.
         $comment = $this->entityManager()->getStorageController('comment')->load($pid);
         // Check if the parent comment is published and belongs to the current nid.
-        if (($comment->status->value == CommentInterface::NOT_PUBLISHED) || ($comment->entity_id->value != $entity->id())) {
+        if (($comment->status->value == COMMENT_NOT_PUBLISHED) || ($comment->entity_id->value != $entity->id())) {
           drupal_set_message($this->t('The comment you are replying to does not exist.'), 'error');
           return new RedirectResponse($this->urlGenerator()->generateFromPath($uri['path'], array('absolute' => TRUE)));
         }
diff --git a/core/modules/comment/lib/Drupal/comment/Entity/Comment.php b/core/modules/comment/lib/Drupal/comment/Entity/Comment.php
index d2c79bd..1b29d84 100644
--- a/core/modules/comment/lib/Drupal/comment/Entity/Comment.php
+++ b/core/modules/comment/lib/Drupal/comment/Entity/Comment.php
@@ -219,7 +219,7 @@ public function preSave(EntityStorageControllerInterface $storage_controller) {
     parent::preSave($storage_controller);
 
     if (!isset($this->status->value)) {
-      $this->status->value = \Drupal::currentUser()->hasPermission('skip comment approval') ? CommentInterface::PUBLISHED : CommentInterface::NOT_PUBLISHED;
+      $this->status->value = \Drupal::currentUser()->hasPermission('skip comment approval') ? COMMENT_PUBLISHED : COMMENT_NOT_PUBLISHED;
     }
     if ($this->isNew()) {
       // Add the comment to database. This next section builds the thread field.
@@ -306,7 +306,7 @@ public function postSave(EntityStorageControllerInterface $storage_controller, $
     $this->releaseThreadLock();
     // Update the {comment_entity_statistics} table prior to executing the hook.
     $storage_controller->updateEntityStatistics($this);
-    if ($this->status->value == CommentInterface::PUBLISHED) {
+    if ($this->status->value == COMMENT_PUBLISHED) {
       module_invoke_all('comment_publish', $this);
     }
   }
diff --git a/core/modules/comment/lib/Drupal/comment/Plugin/Action/PublishComment.php b/core/modules/comment/lib/Drupal/comment/Plugin/Action/PublishComment.php
index 9c11291..93b9a99 100644
--- a/core/modules/comment/lib/Drupal/comment/Plugin/Action/PublishComment.php
+++ b/core/modules/comment/lib/Drupal/comment/Plugin/Action/PublishComment.php
@@ -10,7 +10,6 @@
 use Drupal\Core\Annotation\Action;
 use Drupal\Core\Annotation\Translation;
 use Drupal\Core\Action\ActionBase;
-use Drupal\comment\CommentInterface;
 
 /**
  * Publishes a comment.
@@ -27,7 +26,7 @@ class PublishComment extends ActionBase {
    * {@inheritdoc}
    */
   public function execute($comment = NULL) {
-    $comment->status->value = CommentInterface::PUBLISHED;
+    $comment->status->value = COMMENT_PUBLISHED;
     $comment->save();
   }
 
diff --git a/core/modules/comment/lib/Drupal/comment/Plugin/Action/UnpublishByKeywordComment.php b/core/modules/comment/lib/Drupal/comment/Plugin/Action/UnpublishByKeywordComment.php
index f8350cc..b7d735e 100644
--- a/core/modules/comment/lib/Drupal/comment/Plugin/Action/UnpublishByKeywordComment.php
+++ b/core/modules/comment/lib/Drupal/comment/Plugin/Action/UnpublishByKeywordComment.php
@@ -10,7 +10,6 @@
 use Drupal\Core\Annotation\Action;
 use Drupal\Core\Annotation\Translation;
 use Drupal\Core\Action\ConfigurableActionBase;
-use Drupal\comment\CommentInterface;
 
 /**
  * Unpublishes a comment containing certain keywords.
@@ -31,7 +30,7 @@ public function execute($comment = NULL) {
     $text = drupal_render($build);
     foreach ($this->configuration['keywords'] as $keyword) {
       if (strpos($text, $keyword) !== FALSE) {
-        $comment->status->value = CommentInterface::NOT_PUBLISHED;
+        $comment->status->value = COMMENT_NOT_PUBLISHED;
         $comment->save();
         break;
       }
diff --git a/core/modules/comment/lib/Drupal/comment/Plugin/Action/UnpublishComment.php b/core/modules/comment/lib/Drupal/comment/Plugin/Action/UnpublishComment.php
index 29a0b97..4857d3e 100644
--- a/core/modules/comment/lib/Drupal/comment/Plugin/Action/UnpublishComment.php
+++ b/core/modules/comment/lib/Drupal/comment/Plugin/Action/UnpublishComment.php
@@ -10,7 +10,6 @@
 use Drupal\Core\Annotation\Action;
 use Drupal\Core\Annotation\Translation;
 use Drupal\Core\Action\ActionBase;
-use Drupal\comment\CommentInterface;
 
 /**
  * Unpublishes a comment.
@@ -27,7 +26,7 @@ class UnpublishComment extends ActionBase {
    * {@inheritdoc}
    */
   public function execute($comment = NULL) {
-    $comment->status->value = CommentInterface::NOT_PUBLISHED;
+    $comment->status->value = COMMENT_NOT_PUBLISHED;
     $comment->save();
   }
 
diff --git a/core/modules/comment/lib/Drupal/comment/Plugin/entity_reference/selection/CommentSelection.php b/core/modules/comment/lib/Drupal/comment/Plugin/entity_reference/selection/CommentSelection.php
index 83ebc37..13ce3d0 100644
--- a/core/modules/comment/lib/Drupal/comment/Plugin/entity_reference/selection/CommentSelection.php
+++ b/core/modules/comment/lib/Drupal/comment/Plugin/entity_reference/selection/CommentSelection.php
@@ -9,7 +9,6 @@
 
 use Drupal\Core\Annotation\Translation;
 use Drupal\Core\Database\Query\SelectInterface;
-use Drupal\comment\CommentInterface;
 use Drupal\entity_reference\Annotation\EntityReferenceSelection;
 use Drupal\entity_reference\Plugin\entity_reference\selection\SelectionBase;
 
@@ -36,7 +35,7 @@ public function buildEntityQuery($match = NULL, $match_operator = 'CONTAINS') {
     // core requires us to also know about the concept of 'published' and
     // 'unpublished'.
     if (!user_access('administer comments')) {
-      $query->condition('status', CommentInterface::PUBLISHED);
+      $query->condition('status', COMMENT_PUBLISHED);
     }
     return $query;
   }
diff --git a/core/modules/comment/lib/Drupal/comment/Plugin/views/field/LinkApprove.php b/core/modules/comment/lib/Drupal/comment/Plugin/views/field/LinkApprove.php
index 6344b9e..5fd785a 100644
--- a/core/modules/comment/lib/Drupal/comment/Plugin/views/field/LinkApprove.php
+++ b/core/modules/comment/lib/Drupal/comment/Plugin/views/field/LinkApprove.php
@@ -7,7 +7,6 @@
 
 namespace Drupal\comment\Plugin\views\field;
 
-use Drupal\comment\CommentInterface;
 use Drupal\views\ResultRow;
 use Drupal\Component\Annotation\PluginID;
 
@@ -40,7 +39,7 @@ protected function renderLink($data, ResultRow $values) {
     $status = $this->getValue($values, 'status');
 
     // Don't show an approve link on published nodes.
-    if ($status == CommentInterface::PUBLISHED) {
+    if ($status == COMMENT_PUBLISHED) {
       return;
     }
 
diff --git a/core/modules/comment/lib/Drupal/comment/Plugin/views/field/NodeNewComments.php b/core/modules/comment/lib/Drupal/comment/Plugin/views/field/NodeNewComments.php
index 270136e..3ce1d29 100644
--- a/core/modules/comment/lib/Drupal/comment/Plugin/views/field/NodeNewComments.php
+++ b/core/modules/comment/lib/Drupal/comment/Plugin/views/field/NodeNewComments.php
@@ -9,7 +9,6 @@
 
 use Drupal\Component\Annotation\PluginID;
 use Drupal\Core\Database\Connection;
-use Drupal\comment\CommentInterface;
 use Drupal\views\Plugin\views\field\Numeric;
 use Drupal\views\Plugin\views\display\DisplayPluginBase;
 use Drupal\views\ResultRow;
@@ -122,7 +121,7 @@ public function preRender(&$values) {
       $result = $this->database->query("SELECT n.nid, COUNT(c.cid) as num_comments FROM {node} n INNER JOIN {comment} c ON n.nid = c.entity_id AND c.entity_type = 'node'
         LEFT JOIN {history} h ON h.nid = n.nid AND h.uid = :h_uid WHERE n.nid IN (:nids)
         AND c.changed > GREATEST(COALESCE(h.timestamp, :timestamp), :timestamp) AND c.status = :status GROUP BY n.nid", array(
-        ':status' => CommentInterface::PUBLISHED,
+        ':status' => COMMENT_PUBLISHED,
         ':h_uid' => $user->id(),
         ':nids' => $nids,
         ':timestamp' => HISTORY_READ_LIMIT,
diff --git a/core/modules/comment/lib/Drupal/comment/Tests/CommentActionsTest.php b/core/modules/comment/lib/Drupal/comment/Tests/CommentActionsTest.php
index ea892c8..94a1651 100644
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentActionsTest.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentActionsTest.php
@@ -7,8 +7,6 @@
 
 namespace Drupal\comment\Tests;
 
-use Drupal\comment\CommentInterface;
-
 /**
  * Tests actions provided by the Comment module.
  */
@@ -41,12 +39,12 @@ function testCommentPublishUnpublishActions() {
     // Unpublish a comment.
     $action = entity_load('action', 'comment_unpublish_action');
     $action->execute(array($comment));
-    $this->assertEqual($comment->status->value, CommentInterface::NOT_PUBLISHED, 'Comment was unpublished');
+    $this->assertEqual($comment->status->value, COMMENT_NOT_PUBLISHED, 'Comment was unpublished');
 
     // Publish a comment.
     $action = entity_load('action', 'comment_publish_action');
     $action->execute(array($comment));
-    $this->assertEqual($comment->status->value, CommentInterface::PUBLISHED, 'Comment was published');
+    $this->assertEqual($comment->status->value, COMMENT_PUBLISHED, 'Comment was published');
   }
 
   /**
@@ -72,10 +70,10 @@ function testCommentUnpublishByKeyword() {
     // Load the full comment so that status is available.
     $comment = comment_load($comment->id());
 
-    $this->assertTrue($comment->status->value == CommentInterface::PUBLISHED, 'The comment status was set to published.');
+    $this->assertTrue($comment->status->value == COMMENT_PUBLISHED, 'The comment status was set to published.');
 
     $action->execute(array($comment));
-    $this->assertTrue($comment->status->value == CommentInterface::NOT_PUBLISHED, 'The comment status was set to not published.');
+    $this->assertTrue($comment->status->value == COMMENT_NOT_PUBLISHED, 'The comment status was set to not published.');
   }
 
 }
diff --git a/core/modules/comment/lib/Drupal/comment/Tests/CommentCSSTest.php b/core/modules/comment/lib/Drupal/comment/Tests/CommentCSSTest.php
index 91b9d45..1e98287 100644
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentCSSTest.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentCSSTest.php
@@ -8,7 +8,6 @@
 namespace Drupal\comment\Tests;
 
 use Drupal\Core\Language\Language;
-use Drupal\comment\CommentInterface;
 
 /**
  * Tests comment CSS classes.
@@ -41,7 +40,7 @@ function testCommentClasses() {
     $parameters = array(
       'node_uid' => array(0, $this->web_user->id()),
       'comment_uid' => array(0, $this->web_user->id(), $this->admin_user->id()),
-      'comment_status' => array(CommentInterface::PUBLISHED, CommentInterface::NOT_PUBLISHED),
+      'comment_status' => array(COMMENT_PUBLISHED, COMMENT_NOT_PUBLISHED),
       'user' => array('anonymous', 'authenticated', 'admin'),
     );
     $permutations = $this->generatePermutations($parameters);
@@ -91,7 +90,7 @@ function testCommentClasses() {
       $this->assertIdentical(1, count($this->xpath('//*[@data-history-node-id="' . $node->id() . '"]')), 'data-history-node-id attribute is set on node.');
 
       // Verify classes if the comment is visible for the current user.
-      if ($case['comment_status'] == CommentInterface::PUBLISHED || $case['user'] == 'admin') {
+      if ($case['comment_status'] == COMMENT_PUBLISHED || $case['user'] == 'admin') {
         // Verify the by-anonymous class.
         $comments = $this->xpath('//*[contains(@class, "comment") and contains(@class, "by-anonymous")]');
         if ($case['comment_uid'] == 0) {
@@ -120,7 +119,7 @@ function testCommentClasses() {
 
       // Verify the unpublished class.
       $comments = $this->xpath('//*[contains(@class, "comment") and contains(@class, "unpublished")]');
-      if ($case['comment_status'] == CommentInterface::NOT_PUBLISHED && $case['user'] == 'admin') {
+      if ($case['comment_status'] == COMMENT_NOT_PUBLISHED && $case['user'] == 'admin') {
         $this->assertTrue(count($comments) == 1, 'unpublished class found.');
       }
       else {
@@ -131,7 +130,7 @@ function testCommentClasses() {
       // drupal.comment-new-indicator library to add a "new" indicator to each
       // comment that was created or changed after the last time the current
       // user read the corresponding node.
-      if ($case['comment_status'] == CommentInterface::PUBLISHED || $case['user'] == 'admin') {
+      if ($case['comment_status'] == COMMENT_PUBLISHED || $case['user'] == 'admin') {
         $this->assertIdentical(1, count($this->xpath('//*[contains(@class, "comment")]/*[@data-comment-timestamp="' . $comment->changed->value . '"]')), 'data-comment-timestamp attribute is set on comment');
         $expectedJS = ($case['user'] !== 'anonymous');
         $this->assertIdentical($expectedJS, isset($settings['ajaxPageState']['js']['core/modules/comment/js/comment-new-indicator.js']), 'drupal.comment-new-indicator library is present.');
diff --git a/core/modules/comment/lib/Drupal/comment/Tests/CommentInterfaceTest.php b/core/modules/comment/lib/Drupal/comment/Tests/CommentInterfaceTest.php
index 1e13ddb..b0311cb 100644
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentInterfaceTest.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentInterfaceTest.php
@@ -7,8 +7,6 @@
 
 namespace Drupal\comment\Tests;
 
-use Drupal\comment\CommentInterface;
-
 /**
  * Tests the comment module administrative and end-user-facing interfaces.
  */
@@ -148,7 +146,7 @@ function testCommentInterface() {
     $this->setCommentsPerPage(50);
 
     // Attempt to reply to an unpublished comment.
-    $reply_loaded->status->value = CommentInterface::NOT_PUBLISHED;
+    $reply_loaded->status->value = COMMENT_NOT_PUBLISHED;
     $reply_loaded->save();
     $this->drupalGet('comment/reply/node/' . $this->node->id() . '/comment/' . $reply_loaded->id());
     $this->assertText(t('The comment you are replying to does not exist.'), 'Replying to an unpublished comment');
diff --git a/core/modules/comment/lib/Drupal/comment/Tests/CommentLinksTest.php b/core/modules/comment/lib/Drupal/comment/Tests/CommentLinksTest.php
index 6eabd64..c529ab9 100644
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentLinksTest.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentLinksTest.php
@@ -8,7 +8,6 @@
 namespace Drupal\comment\Tests;
 
 use Drupal\Core\Language\Language;
-use Drupal\comment\CommentInterface;
 
 /**
  * Tests comment links based on environment configurations.
@@ -147,7 +146,7 @@ function setEnvironment(array $info) {
           'field_name' => 'comment',
           'pid' => 0,
           'uid' => 0,
-          'status' => CommentInterface::PUBLISHED,
+          'status' => COMMENT_PUBLISHED,
           'subject' => $this->randomName(),
           'hostname' => '127.0.0.1',
           'langcode' => Language::LANGCODE_NOT_SPECIFIED,
diff --git a/core/modules/comment/lib/Drupal/comment/Tests/CommentNewIndicatorTest.php b/core/modules/comment/lib/Drupal/comment/Tests/CommentNewIndicatorTest.php
index 17e358c..cdf658a 100644
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentNewIndicatorTest.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentNewIndicatorTest.php
@@ -8,7 +8,6 @@
 namespace Drupal\comment\Tests;
 
 use Drupal\Core\Language\Language;
-use Drupal\comment\CommentInterface;
 
 /**
  * Tests the 'new' marker on comments.
@@ -95,7 +94,7 @@ public function testCommentNewCommentsIndicator() {
       'field_name' => 'comment',
       'pid' => 0,
       'uid' => $this->loggedInUser->id(),
-      'status' => CommentInterface::PUBLISHED,
+      'status' => COMMENT_PUBLISHED,
       'subject' => $this->randomName(),
       'hostname' => '127.0.0.1',
       'langcode' => Language::LANGCODE_NOT_SPECIFIED,
diff --git a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionAccessTest.php b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionAccessTest.php
index 3fb6460..98373ae 100644
--- a/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionAccessTest.php
+++ b/core/modules/entity_reference/lib/Drupal/entity_reference/Tests/EntityReferenceSelectionAccessTest.php
@@ -9,7 +9,6 @@
 
 use Drupal\Core\Field\FieldDefinitionInterface;
 use Drupal\Core\Language\Language;
-use Drupal\comment\CommentInterface;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -408,7 +407,7 @@ public function testCommentHandler() {
         'uid' => 1,
         'cid' => NULL,
         'pid' => 0,
-        'status' => CommentInterface::PUBLISHED,
+        'status' => COMMENT_PUBLISHED,
         'subject' => 'Comment Published <&>',
         'language' => Language::LANGCODE_NOT_SPECIFIED,
       ),
@@ -419,7 +418,7 @@ public function testCommentHandler() {
         'uid' => 1,
         'cid' => NULL,
         'pid' => 0,
-        'status' => CommentInterface::NOT_PUBLISHED,
+        'status' => COMMENT_NOT_PUBLISHED,
         'subject' => 'Comment Unpublished <&>',
         'language' => Language::LANGCODE_NOT_SPECIFIED,
       ),
@@ -430,7 +429,7 @@ public function testCommentHandler() {
         'uid' => 1,
         'cid' => NULL,
         'pid' => 0,
-        'status' => CommentInterface::NOT_PUBLISHED,
+        'status' => COMMENT_NOT_PUBLISHED,
         'subject' => 'Comment Published on Unpublished node <&>',
         'language' => Language::LANGCODE_NOT_SPECIFIED,
       ),
diff --git a/core/modules/forum/lib/Drupal/forum/ForumManager.php b/core/modules/forum/lib/Drupal/forum/ForumManager.php
index 5c530c7..cdf9a5e 100644
--- a/core/modules/forum/lib/Drupal/forum/ForumManager.php
+++ b/core/modules/forum/lib/Drupal/forum/ForumManager.php
@@ -11,7 +11,6 @@
 use Drupal\Core\Database\Connection;
 use Drupal\Core\Entity\EntityManagerInterface;
 use Drupal\Core\StringTranslation\TranslationInterface;
-use Drupal\comment\CommentInterface;
 use Drupal\field\FieldInfo;
 use Drupal\node\NodeInterface;
 
@@ -519,14 +518,14 @@ public function unreadTopics($term, $uid) {
   public function updateIndex($nid) {
     $count = $this->connection->query("SELECT COUNT(cid) FROM {comment} c INNER JOIN {forum_index} i ON c.entity_id = i.nid WHERE c.entity_id = :nid AND c.field_id = 'node__comment_forum' AND c.entity_type = 'node' AND c.status = :status", array(
       ':nid' => $nid,
-      ':status' => CommentInterface::PUBLISHED,
+      ':status' => COMMENT_PUBLISHED,
     ))->fetchField();
 
     if ($count > 0) {
       // Comments exist.
       $last_reply = $this->connection->queryRange("SELECT cid, name, created, uid FROM {comment} WHERE entity_id = :nid AND field_id = 'node__comment_forum' AND entity_type = 'node' AND status = :status ORDER BY cid DESC", 0, 1, array(
         ':nid' => $nid,
-        ':status' => CommentInterface::PUBLISHED,
+        ':status' => COMMENT_PUBLISHED,
       ))->fetchObject();
       $this->connection->update('forum_index')
         ->fields( array(
diff --git a/core/modules/forum/lib/Drupal/forum/Tests/ForumUninstallTest.php b/core/modules/forum/lib/Drupal/forum/Tests/ForumUninstallTest.php
index fed1353..d1f0e65 100644
--- a/core/modules/forum/lib/Drupal/forum/Tests/ForumUninstallTest.php
+++ b/core/modules/forum/lib/Drupal/forum/Tests/ForumUninstallTest.php
@@ -7,7 +7,6 @@
 
 namespace Drupal\forum\Tests;
 
-use Drupal\comment\CommentInterface;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -63,7 +62,7 @@ function testForumUninstallWithField() {
       'field_name' => 'comment_forum',
       'pid' => 0,
       'uid' => 0,
-      'status' => CommentInterface::PUBLISHED,
+      'status' => COMMENT_PUBLISHED,
       'subject' => $this->randomName(),
       'hostname' => '127.0.0.1',
     ));
diff --git a/core/modules/image/image.module b/core/modules/image/image.module
index 5b0d9a3..52c4d53 100644
--- a/core/modules/image/image.module
+++ b/core/modules/image/image.module
@@ -420,12 +420,10 @@ function image_entity_presave(EntityInterface $entity, $type) {
     return;
   }
 
-  if (!empty($entity->settings['default_image']['fid'][0])) {
-    $entity->settings['default_image']['fid'] = $entity->settings['default_image']['fid'][0];
-  }
-  if ($fid = $entity->settings['default_image']['fid']) {
+  $fid = $entity->settings['default_image']['fid'];
+  if ($fid) {
     $original_fid = isset($entity->original) ? $entity->original->settings['default_image']['fid'] : NULL;
-    if ($fid != $original_fid) {
+    if ($entity->settings['default_image']['fid'] != $original_fid) {
       $image = \Drupal::service('image.factory')->get(file_load($fid)->getFileUri());
       $entity->settings['default_image']['width'] = $image->getWidth();
       $entity->settings['default_image']['height'] = $image->getHeight();
@@ -454,15 +452,10 @@ function image_field_entity_update(FieldInterface $field) {
   $prior_field = $field->original;
 
   // The value of a managed_file element can be an array if #extended == TRUE.
-  $fid_new = isset($field->settings['default_image']['fid']['fids']) ? $field->settings['default_image']['fid']['fids'] : $field->settings['default_image']['fid'];
-  $fid_old = isset($prior_field->settings['default_image']['fid']['fids']) ? $prior_field->settings['default_image']['fid']['fids'] : $prior_field->settings['default_image']['fid'];
-  // Ensure that $fid_new and $fid_old are arrays, because the field setting
-  // 'default_image' key 'fid' might be the fallback value 0, see the annotation
-  // block of \Drupal\image\Plugin\Field\FieldType\ImageItem.
-  $fid_old = (array) $fid_old;
-  $fid_new = (array) $fid_new;
+  $fid_new = $field->settings['default_image']['fid'];
+  $fid_old = $prior_field->settings['default_image']['fid'];
 
-  $file_new = $fid_new ? file_load(reset($fid_new)) : FALSE;
+  $file_new = $fid_new ? file_load($fid_new) : FALSE;
 
   if ($fid_new != $fid_old) {
 
@@ -474,7 +467,7 @@ function image_field_entity_update(FieldInterface $field) {
     }
 
     // Is there an old file?
-    if ($fid_old && ($file_old = file_load(reset($fid_old)))) {
+    if ($fid_old && ($file_old = file_load($fid_old))) {
       \Drupal::service('file.usage')->delete($file_old, 'image', 'default_image', $field->uuid);
     }
   }
@@ -499,19 +492,11 @@ function image_field_instance_update(FieldInstanceInterface $field_instance) {
 
   $prior_instance = $field_instance->original;
 
-  // The value of a managed_file element can be an array if the #extended
-  // property is set to TRUE.
   $fid_new = $field_instance->settings['default_image']['fid'];
-  if (isset($fid_new['fids'])) {
-    $fid_new = $fid_new['fids'];
-  }
   $fid_old = $prior_instance->settings['default_image']['fid'];
-  if (isset($fid_old['fids'])) {
-    $fid_old = $fid_old['fids'];
-  }
 
   // If the old and new files do not match, update the default accordingly.
-  $file_new = $fid_new ? file_load($fid_new[0]) : FALSE;
+  $file_new = $fid_new ? file_load($fid_new) : FALSE;
   if ($fid_new != $fid_old) {
     // Save the new file, if present.
     if ($file_new) {
@@ -520,7 +505,7 @@ function image_field_instance_update(FieldInstanceInterface $field_instance) {
       \Drupal::service('file.usage')->add($file_new, 'image', 'default_image', $field_instance->uuid);
     }
     // Delete the old file, if present.
-    if ($fid_old && ($file_old = file_load($fid_old[0]))) {
+    if ($fid_old && ($file_old = file_load($fid_old))) {
       \Drupal::service('file.usage')->delete($file_old, 'image', 'default_image', $field_instance->uuid);
     }
   }
@@ -543,8 +528,8 @@ function image_field_entity_delete(FieldInterface $field) {
   }
 
   // The value of a managed_file element can be an array if #extended == TRUE.
-  $fid = (isset($field->settings['default_image']['fid']['fids']) ? $field->settings['default_image']['fid']['fids'] : $field->settings['default_image']['fid']);
-  if ($fid && ($file = file_load($fid[0]))) {
+  $fid = $field->settings['default_image']['fid'];
+  if ($fid && ($file = file_load($fid))) {
     \Drupal::service('file.usage')->delete($file, 'image', 'default_image', $field->uuid);
   }
 }
@@ -559,12 +544,8 @@ function image_field_instance_delete(FieldInstanceInterface $field_instance) {
     return;
   }
 
-  // The value of a managed_file element can be an array if the #extended
-  // property is set to TRUE.
+  // The value of a managed_file element can be an array if #extended == TRUE.
   $fid = $field_instance->settings['default_image']['fid'];
-  if (is_array($fid)) {
-    $fid = $fid['fid'];
-  }
 
   // Remove the default image when the instance is deleted.
   if ($fid && ($file = file_load($fid))) {
diff --git a/core/modules/image/lib/Drupal/image/Plugin/Field/FieldType/ImageItem.php b/core/modules/image/lib/Drupal/image/Plugin/Field/FieldType/ImageItem.php
index b1e56f3..a8ef483 100644
--- a/core/modules/image/lib/Drupal/image/Plugin/Field/FieldType/ImageItem.php
+++ b/core/modules/image/lib/Drupal/image/Plugin/Field/FieldType/ImageItem.php
@@ -335,6 +335,7 @@ protected function defaultImageForm(array &$element, array $settings) {
       '#description' => t('Image to be shown if no image is uploaded.'),
       '#default_value' => empty($settings['default_image']['fid']) ? array() : array($settings['default_image']['fid']),
       '#upload_location' => $settings['uri_scheme'] . '://default_images/',
+      '#element_validate' => array(array($this, 'validateDefaultImageForm')),
     );
     $element['default_image']['alt'] = array(
       '#type' => 'textfield',
@@ -361,6 +362,34 @@ protected function defaultImageForm(array &$element, array $settings) {
   }
 
   /**
+   * Validates the managed_file element for the default Image form.
+   *
+   * This function ensures the fid is a scalar value and not an array. It is
+   * assigned as a #element_validate callback in
+   * \Drupal\image\Plugin\Field\FieldType\ImageItem::defaultImageForm().
+   *
+   * @param array $element
+   *   The form element to process.
+   * @param array $form_state
+   *   The form state.
+   */
+  public function validateDefaultImageForm(array &$element, array &$form_state) {
+    // Call the original validator to ensure referencing an existing file is
+    // only allowed if there are existing references.
+    file_managed_file_validate($element, $form_state);
+
+    // Consolidate the array value of this field to a single FID as #extended
+    // for default image is not TRUE and this is a single value.
+    if (isset($element['fids']['#value'][0])) {
+      $value = $element['fids']['#value'][0];
+    }
+    else {
+      $value = 0;
+    }
+    \Drupal::formBuilder()->setValue($element, $value, $form_state);
+  }
+
+  /**
    * {@inheritdoc}
    */
   public function isDisplayed() {
diff --git a/core/modules/image/lib/Drupal/image/Tests/ImageFieldDefaultImagesTest.php b/core/modules/image/lib/Drupal/image/Tests/ImageFieldDefaultImagesTest.php
index da68885..8244fa0 100644
--- a/core/modules/image/lib/Drupal/image/Tests/ImageFieldDefaultImagesTest.php
+++ b/core/modules/image/lib/Drupal/image/Tests/ImageFieldDefaultImagesTest.php
@@ -33,6 +33,14 @@ public static function getInfo() {
   public function testDefaultImages() {
     // Create files to use as the default images.
     $files = $this->drupalGetTestFiles('image');
+    // Create 10 files so the default image fids are not a single value.
+    for ($i = 1; $i <= 10; $i++) {
+      $filename = $this->randomName() . "$i";
+      $desired_filepath = 'public://' . $filename;
+      file_unmanaged_copy($files[0]->uri, $desired_filepath, FILE_EXISTS_ERROR);
+      $file = entity_create('file', array('uri' => $desired_filepath, 'filename' => $filename, 'name' => $filename));
+      $file->save();
+    }
     $default_images = array();
     foreach (array('field', 'instance', 'instance2', 'field_new', 'instance_new') as $image_target) {
       $file = entity_create('file', (array) array_pop($files));
@@ -173,7 +181,7 @@ public function testDefaultImages() {
     );
 
     // Upload a new default for the field.
-    $field->settings['default_image']['fid'] = array($default_images['field_new']->id());
+    $field->settings['default_image']['fid'] = $default_images['field_new']->id();
     $field->save();
 
     // Confirm that the new default is used on the article field settings form.
diff --git a/core/modules/node/lib/Drupal/node/Tests/NodeAccessPagerTest.php b/core/modules/node/lib/Drupal/node/Tests/NodeAccessPagerTest.php
index 74cd9c7..579626a 100644
--- a/core/modules/node/lib/Drupal/node/Tests/NodeAccessPagerTest.php
+++ b/core/modules/node/lib/Drupal/node/Tests/NodeAccessPagerTest.php
@@ -8,7 +8,6 @@
 namespace Drupal\node\Tests;
 
 use Drupal\Core\Language\Language;
-use Drupal\comment\CommentInterface;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -56,7 +55,7 @@ public function testCommentPager() {
         'comment_body' => array(
           array('value' => $this->randomName()),
         ),
-        'status' => CommentInterface::PUBLISHED,
+        'status' => COMMENT_PUBLISHED,
       ));
       $comment->save();
     }
diff --git a/core/modules/system/lib/Drupal/system/Tests/Theme/EntityFilteringThemeTest.php b/core/modules/system/lib/Drupal/system/Tests/Theme/EntityFilteringThemeTest.php
index 8a96631..411f6fe 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Theme/EntityFilteringThemeTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Theme/EntityFilteringThemeTest.php
@@ -7,7 +7,6 @@
 
 namespace Drupal\system\Tests\Theme;
 
-use Drupal\comment\CommentInterface;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -113,7 +112,7 @@ function setUp() {
       'entity_id' => $this->node->id(),
       'entity_type' => 'node',
       'field_name' => 'comment',
-      'status' => CommentInterface::PUBLISHED,
+      'status' => COMMENT_PUBLISHED,
       'subject' => $this->xss_label,
       'comment_body' => array($this->randomName()),
     ));
diff --git a/core/modules/tracker/lib/Drupal/tracker/Tests/TrackerTest.php b/core/modules/tracker/lib/Drupal/tracker/Tests/TrackerTest.php
index 0abd95e..7a3983e 100644
--- a/core/modules/tracker/lib/Drupal/tracker/Tests/TrackerTest.php
+++ b/core/modules/tracker/lib/Drupal/tracker/Tests/TrackerTest.php
@@ -7,7 +7,6 @@
 
 namespace Drupal\tracker\Tests;
 
-use Drupal\comment\CommentInterface;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -122,7 +121,7 @@ function testTrackerUser() {
     // Verify that unpublished comments are removed from the tracker.
     $admin_user = $this->drupalCreateUser(array('post comments', 'administer comments', 'access user profiles'));
     $this->drupalLogin($admin_user);
-    $this->drupalPostForm('comment/1/edit', array('status' => CommentInterface::NOT_PUBLISHED), t('Save'));
+    $this->drupalPostForm('comment/1/edit', array('status' => COMMENT_NOT_PUBLISHED), t('Save'));
     $this->drupalGet('user/' . $this->user->id() . '/track');
     $this->assertNoText($other_published_my_comment->label(), 'Unpublished comments are not counted on the tracker listing.');
   }
diff --git a/core/modules/tracker/tracker.module b/core/modules/tracker/tracker.module
index b1be041..eca8ccc 100644
--- a/core/modules/tracker/tracker.module
+++ b/core/modules/tracker/tracker.module
@@ -6,7 +6,6 @@
  */
 
 use Drupal\Core\Entity\EntityInterface;
-use Drupal\comment\CommentInterface;
 use Drupal\node\NodeInterface;
 use Drupal\Core\Session\AccountInterface;
 
@@ -93,7 +92,7 @@ function tracker_cron() {
         ->condition('c.entity_id', $row->nid)
         ->condition('c.entity_type', 'node')
         ->condition('c.uid', $row->uid, '<>')
-        ->condition('c.status', CommentInterface::PUBLISHED);
+        ->condition('c.status', COMMENT_PUBLISHED);
 
       // Insert the user-level data for the commenters (except if a commenter
       // is the node's author).
@@ -194,7 +193,7 @@ function tracker_node_predelete(EntityInterface $node, $arg = 0) {
 function tracker_comment_update($comment) {
   // $comment->save() calls hook_comment_publish() for all published comments
   // so we need to handle all other values here.
-  if ($comment->status->value != CommentInterface::PUBLISHED && $comment->entity_type->value == 'node') {
+  if ($comment->status->value != COMMENT_PUBLISHED && $comment->entity_type->value == 'node') {
     _tracker_remove($comment->entity_id->target_id, $comment->uid->target_id, $comment->changed->value);
   }
 }
@@ -286,7 +285,7 @@ function _tracker_calculate_changed($nid) {
   $changed = db_query('SELECT changed FROM {node_field_data} WHERE nid = :nid AND default_langcode = 1 ORDER BY changed DESC', array(':nid' => $nid), array('target' => 'slave'))->fetchField();
   $latest_comment = db_query_range("SELECT cid, changed FROM {comment} WHERE entity_type = 'node' AND entity_id = :nid AND status = :status ORDER BY changed DESC", 0, 1, array(
     ':nid' => $nid,
-    ':status' => CommentInterface::PUBLISHED,
+    ':status' => COMMENT_PUBLISHED,
   ), array('target' => 'slave'))->fetchObject();
   if ($latest_comment && $latest_comment->changed > $changed) {
     $changed = $latest_comment->changed;
@@ -320,7 +319,7 @@ function _tracker_remove($nid, $uid = NULL, $changed = NULL) {
       $keep_subscription = db_query_range("SELECT COUNT(*) FROM {comment} WHERE entity_type = 'node' AND entity_id = :nid AND uid = :uid AND status = :status", 0, 1, array(
         ':nid' => $nid,
         ':uid' => $uid,
-        ':status' => CommentInterface::PUBLISHED,
+        ':status' => COMMENT_PUBLISHED,
       ))->fetchField();
     }