diff --git a/core/modules/config/config.admin.inc b/core/modules/config/config.admin.inc
index 99e4ee9..cf8ed0c 100644
--- a/core/modules/config/config.admin.inc
+++ b/core/modules/config/config.admin.inc
@@ -5,94 +5,10 @@
  * Admin page callbacks for the config module.
  */
 
-use Drupal\Core\Config\StorageInterface;
 use Drupal\Core\Ajax\AjaxResponse;
 use Drupal\Core\Ajax\OpenModalDialogCommand;
 
 /**
- * Helper function to construct the storage changes in a configuration synchronization form.
- *
- * @param array $form
- *   The form structure to add to. Passed by reference.
- * @param array $form_state
- *   The current state of the form. Passed by reference.
- * @param Drupal\Core\Config\StorageInterface $source_storage
- *   The source storage to retrieve differences from.
- * @param Drupal\Core\Config\StorageInterface $target_storage
- *   The target storage to compare differences to.
- */
-function config_admin_sync_form(array &$form, array &$form_state, StorageInterface $source_storage, StorageInterface $target_storage) {
-  $source_list = $source_storage->listAll();
-  if (empty($source_list)) {
-    $form['no_changes'] = array(
-      '#markup' => t('There is no configuration to import.'),
-    );
-    $form['actions']['#access'] = FALSE;
-    return $form;
-  }
-
-  $config_changes = config_sync_get_changes($source_storage, $target_storage);
-  if (empty($config_changes)) {
-    $form['no_changes'] = array(
-      '#markup' => t('There are no configuration changes.'),
-    );
-    return $form;
-  }
-
-  // Add the AJAX library to the form for dialog support.
-  $form['#attached']['library'][] = array('system', 'drupal.ajax');
-
-  foreach ($config_changes as $config_change_type => $config_files) {
-    if (empty($config_files)) {
-      continue;
-    }
-
-    // @todo A table caption would be more appropriate, but does not have the
-    //   visual importance of a heading.
-    $form[$config_change_type]['heading'] = array(
-      '#theme' => 'html_tag__h3',
-      '#tag' => 'h3',
-    );
-    switch ($config_change_type) {
-      case 'create':
-        $form[$config_change_type]['heading']['#value'] = format_plural(count($config_files), '@count new', '@count new');
-        break;
-
-      case 'change':
-        $form[$config_change_type]['heading']['#value'] = format_plural(count($config_files), '@count changed', '@count changed');
-        break;
-
-      case 'delete':
-        $form[$config_change_type]['heading']['#value'] = format_plural(count($config_files), '@count removed', '@count removed');
-        break;
-    }
-    $form[$config_change_type]['list'] = array(
-      '#theme' => 'table',
-      '#header' => array('Name', 'Operations'),
-    );
-
-    foreach ($config_files as $config_file) {
-      $links['view_diff'] = array(
-        'title' => t('View differences'),
-        'href' => 'admin/config/development/sync/diff/' . $config_file,
-        'attributes' => array(
-          'class' => array('use-ajax'),
-        ),
-      );
-      $form[$config_change_type]['list']['#rows'][] = array(
-        'name' => $config_file,
-        'operations' => array(
-          'data' => array(
-            '#type' => 'operations',
-            '#links' => $links,
-          ),
-        ),
-      );
-    }
-  }
-}
-
-/**
  * Page callback: Shows diff of specificed configuration file.
  *
  * @param string $config_file
diff --git a/core/modules/config/lib/Drupal/config/Form/ConfigAdminImportForm.php b/core/modules/config/lib/Drupal/config/Form/ConfigAdminImportForm.php
index 8999301..6b4a12e 100644
--- a/core/modules/config/lib/Drupal/config/Form/ConfigAdminImportForm.php
+++ b/core/modules/config/lib/Drupal/config/Form/ConfigAdminImportForm.php
@@ -56,7 +56,7 @@ public function __construct(StorageInterface $source_storage, StorageInterface $
   }
 
   /**
-   * Implements \Drupal\Core\ControllerInterface::create().
+   * {@inheritdoc}
    */
   public static function create(ContainerInterface $container) {
     return new static(
@@ -67,16 +67,84 @@ public static function create(ContainerInterface $container) {
   }
 
   /**
-   * Implements \Drupal\Core\Form\FormInterface::getFormID().
+   * {@inheritdoc}
    */
   public function getFormID() {
     return 'config_admin_import';
   }
 
   /**
-   * Implements \Drupal\Core\Form\FormInterface::buildForm().
+   * {@inheritdoc}
    */
   public function buildForm(array $form, array &$form_state) {
+    $source_list = $this->sourceStorage->listAll();
+    if (empty($source_list)) {
+      $form['no_changes'] = array(
+        '#markup' => t('There is no configuration to import.'),
+      );
+      return $form;
+    }
+
+    $config_changes = config_sync_get_changes($this->sourceStorage, $this->targetStorage);
+    if (empty($config_changes)) {
+      $form['no_changes'] = array(
+        '#markup' => t('There are no configuration changes.'),
+      );
+      return $form;
+    }
+
+    // Add the AJAX library to the form for dialog support.
+    $form['#attached']['library'][] = array('system', 'drupal.ajax');
+
+    foreach ($config_changes as $config_change_type => $config_files) {
+      if (empty($config_files)) {
+        continue;
+      }
+
+      // @todo A table caption would be more appropriate, but does not have the
+      //   visual importance of a heading.
+      $form[$config_change_type]['heading'] = array(
+        '#theme' => 'html_tag__h3',
+        '#tag' => 'h3',
+      );
+      switch ($config_change_type) {
+        case 'create':
+          $form[$config_change_type]['heading']['#value'] = format_plural(count($config_files), '@count new', '@count new');
+          break;
+
+        case 'change':
+          $form[$config_change_type]['heading']['#value'] = format_plural(count($config_files), '@count changed', '@count changed');
+          break;
+
+        case 'delete':
+          $form[$config_change_type]['heading']['#value'] = format_plural(count($config_files), '@count removed', '@count removed');
+          break;
+      }
+      $form[$config_change_type]['list'] = array(
+        '#theme' => 'table',
+        '#header' => array('Name', 'Operations'),
+      );
+
+      foreach ($config_files as $config_file) {
+        $links['view_diff'] = array(
+          'title' => t('View differences'),
+          'href' => 'admin/config/development/sync/diff/' . $config_file,
+          'attributes' => array(
+            'class' => array('use-ajax'),
+          ),
+        );
+        $form[$config_change_type]['list']['#rows'][] = array(
+          'name' => $config_file,
+          'operations' => array(
+            'data' => array(
+              '#type' => 'operations',
+              '#links' => $links,
+            ),
+          ),
+        );
+      }
+    }
+
     $form['actions'] = array(
       '#type' => 'actions',
     );
@@ -85,25 +153,23 @@ public function buildForm(array $form, array &$form_state) {
       '#value' => t('Import all'),
     );
 
-    module_load_include('inc', 'config', 'config.admin');
-    config_admin_sync_form($form, $form_state, $this->sourceStorage, $this->targetStorage);
     return $form;
   }
 
   /**
-   * Implements \Drupal\Core\Form\FormInterface::validateForm().
+   * {@inheritdoc}
    */
   public function validateForm(array &$form, array &$form_state) {
   }
 
   /**
-   * Implements \Drupal\Core\Form\FormInterface::validateForm().
+   * {@inheritdoc}
    */
   public function submitForm(array &$form, array &$form_state) {
     if (!$this->lock->lockMayBeAvailable(CONFIG_IMPORT_LOCK)) {
       drupal_set_message(t('Another request may be synchronizing configuration already.'));
     }
-    else if (config_import()) {
+    elseif (config_import()) {
       // Once a sync completes, we empty the staging directory. This prevents
       // changes from being accidentally overwritten by stray files getting
       // imported later.
@@ -119,4 +185,5 @@ public function submitForm(array &$form, array &$form_state) {
       drupal_set_message(t('The import failed due to an error. Any errors have been logged.'), 'error');
     }
   }
+
 }