192-168-1-5:drupal8 admin$ git remote
origin
192-168-1-5:drupal8 admin$ git fetch origin
192-168-1-5:drupal8 admin$
192-168-1-5:drupal8 admin$
192-168-1-5:drupal8 admin$ git status
# On branch 8.x
nothing to commit, working directory clean
192-168-1-5:drupal8 admin$
192-168-1-5:drupal8 admin$
192-168-1-5:drupal8 admin$ git merge origin
Already up-to-date.
192-168-1-5:drupal8 admin$
192-168-1-5:drupal8 admin$ git checkout -b 1945226-menu-language-selector-b
Switched to a new branch '1945226-menu-language-selector-b'
192-168-1-5:drupal8 admin$ pwd
/Users/admin/drupal8
192-168-1-5:drupal8 admin$ curl -O http://drupal.org/files/drupal-1945226-Add-language-selector-on-menus-3.patch
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  3801  100  3801    0     0   3177      0  0:00:01  0:00:01 --:--:--  8191
192-168-1-5:drupal8 admin$ git apply drupal-1945226-Add-language-selector-on-menus-3.patch
192-168-1-5:drupal8 admin$
192-168-1-5:drupal8 admin$ git status
# On branch 1945226-menu-language-selector-b
# Changes not staged for commit:
#   (use "git add <file>..." to update what will be committed)
#   (use "git checkout -- <file>..." to discard changes in working directory)
#
#	modified:   core/modules/menu/lib/Drupal/menu/MenuFormController.php
#
# Untracked files:
#   (use "git add <file>..." to include in what will be committed)
#
#	sites/default/files/
#	sites/default/settings.php
no changes added to commit (use "git add" and/or "git commit -a")
192-168-1-5:drupal8 admin$ git diff
diff --git a/core/modules/menu/lib/Drupal/menu/MenuFormController.php b/core/modules/menu/lib/Drupal/menu/MenuFormController.php
index ff42a20..e229451 100644
--- a/core/modules/menu/lib/Drupal/menu/MenuFormController.php
+++ b/core/modules/menu/lib/Drupal/menu/MenuFormController.php
@@ -63,6 +63,31 @@ public function form(array $form, array &$form_state, EntityInterface $menu) {
       $form['links'] = menu_overview_form($form['links'], $form_state);
     }

+    // $form['langcode'] is not wrapped in an if (module_exists('language'))
+    // check because the language_select form element works also without the
+    // language module being installed.
+    // http://drupal.org/node/1749954 documents the new element.
+    $form['langcode'] = array(
+      '#type' => 'language_select',
+      '#title' => t('Menu language'),
+      '#languages' => LANGUAGE_ALL,
+      '#default_value' => $menu->langcode,
+    );
+    if (module_exists('language')) {
+      $form['default_menu_items_language'] = array(
+        '#type' => 'details',
+        '#title' => t('Menu items language'),
+      );
+      $form['default_menu_items_language']['default_language'] = array(
+        '#type' => 'language_configuration',
+        '#entity_information' => array(
+          'entity_type' => 'menu_item',
+          'bundle' => $menu->id(),
+        ),
+        '#default_value' => language_get_default_configuration('menu_item', $menu->id()),
+      );
+    }
+
     return $form;
   }