diff -u b/core/includes/theme.inc b/core/includes/theme.inc
--- b/core/includes/theme.inc
+++ b/core/includes/theme.inc
@@ -2100,7 +2100,7 @@
   $variables['base_path']         = base_path();
   $variables['front_page']        = url();
   $variables['language']          = $language_interface;
-  $variables['language']->dir     = $language_interface->direction ? 'rtl' : 'ltr';
+  $variables['language']->dir     = $language_interface->getDirection() ? 'rtl' : 'ltr';
   $variables['logo']              = theme_get_setting('logo.url');
   $variables['site_name']         = (theme_get_setting('features.name') ? String::checkPlain($site_config->get('name')) : '');
   $variables['site_slogan']       = (theme_get_setting('features.slogan') ? Xss::filterAdmin($site_config->get('slogan')) : '');
@@ -2123,7 +2123,7 @@
   $variables['base_path']         = base_path();
   $variables['front_page']        = url();
   $variables['language']          = $language_interface;
-  $variables['language']->dir     = $language_interface->getDirection() ? 'rtl' : 'ltr';
+  $variables['language']->dir     = $language_interface->direction ? 'rtl' : 'ltr';
   $variables['logo']              = theme_get_setting('logo.url');
   $variables['site_name']         = (theme_get_setting('features.name') ? String::checkPlain($site_config->get('name')) : '');
   $variables['site_slogan']       = (theme_get_setting('features.slogan') ? Xss::filterAdmin($site_config->get('slogan')) : '');
diff -u b/core/includes/update.inc b/core/includes/update.inc
--- b/core/includes/update.inc
+++ b/core/includes/update.inc
@@ -13,6 +13,8 @@
 use Drupal\Core\Config\FileStorage;
 use Drupal\Core\Config\ConfigException;
 use Drupal\Core\DrupalKernel;
+use Drupal\Core\Language\Language;
+use Drupal\Core\Language\LanguageInterface;
 use Drupal\Core\Page\DefaultHtmlPageRenderer;
 use Drupal\Core\Utility\Error;
 use Drupal\Component\Uuid\Uuid;
@@ -829,7 +831,7 @@
         $langcode = substr($langcode_config_name, strlen('language.entity.'));
         $info = \Drupal::config($langcode_config_name)->get();
         $languages[$langcode] = new Language(array(
-          'default' => ($info['id'] == $default->id),
+          'default' => ($info['id'] == $default->getId()),
           'name' => $info['label'],
           'id' => $info['id'],
           'direction' => $info['direction'],
@@ -837,13 +839,13 @@
           'weight' => $info['weight'],
         ));
       }
-      LanguageInterface::sort($languages);
+      uasort($languages, '\Drupal\Core\Language\Language::sort');
     }
     else {
       // No language module, so use the default language only.
-      $languages = array($default->id => $default);
+      $languages = array($default->getId() => $default);
       // Add the special languages, they will be filtered later if needed.
-      $languages += \Drupal::languageManager()->getDefaultLockedLanguages($default->weight);
+      $languages += \Drupal::languageManager()->getDefaultLockedLanguages($default->getWeight());
     }
   }
 
diff -u b/core/lib/Drupal/Core/Language/Language.php b/core/lib/Drupal/Core/Language/Language.php
--- b/core/lib/Drupal/Core/Language/Language.php
+++ b/core/lib/Drupal/Core/Language/Language.php
@@ -219,11 +219,21 @@
   /**
    * Sort language objects.
    *
-   * @param array $languages
-   *   The array of language objects keyed by langcode.
+   * This is a sort() callback.
+   *
+   * @param \Drupal\Core\Language\LanguageInterface $a
+   * @param \Drupal\Core\Language\LanguageInterface $b
+   *
+   * @return int
+   *   -1, 0, or 1.
    */
-  public static function sort(&$languages) {
-    uasort($languages, 'Drupal\Component\Utility\SortArray::sortByWeightAndTitleKey');
+  public static function sort(LanguageInterface $a, LanguageInterface $b) {
+    if ($a->getWeight() == $b->getWeight()) {
+      return strnatcasecmp($a->getName(), $b->getName());
+    }
+    else {
+      return $a->getWeight() < $b->getWeight() ? -1 : 1;
+    }
   }
 
 }
diff -u b/core/modules/aggregator/lib/Drupal/aggregator/Tests/FeedLanguageTest.php b/core/modules/aggregator/lib/Drupal/aggregator/Tests/FeedLanguageTest.php
--- b/core/modules/aggregator/lib/Drupal/aggregator/Tests/FeedLanguageTest.php
+++ b/core/modules/aggregator/lib/Drupal/aggregator/Tests/FeedLanguageTest.php
@@ -24,7 +24,7 @@
   /**
    * List of langcodes.
    *
-   * @var array
+   * @var \Drupal\Core\Language\LanguageInterface[]
    */
   protected $langcodes = array();
 
@@ -58,12 +58,12 @@
     /** @var \Drupal\aggregator\FeedInterface[] $feeds */
     $feeds = array();
     // Create feeds.
-    $feeds[1] = $this->createFeed(NULL, array('langcode' => $this->langcodes[1]->id));
-    $feeds[2] = $this->createFeed(NULL, array('langcode' => $this->langcodes[2]->id));
+    $feeds[1] = $this->createFeed(NULL, array('langcode' => $this->langcodes[1]->getId()));
+    $feeds[2] = $this->createFeed(NULL, array('langcode' => $this->langcodes[2]->getId()));
 
     // Make sure that the language has been assigned.
-    $this->assertEqual($feeds[1]->language()->getId(), $this->langcodes[1]->id);
-    $this->assertEqual($feeds[2]->language()->getId(), $this->langcodes[2]->id);
+    $this->assertEqual($feeds[1]->language()->getId(), $this->langcodes[1]->getId());
+    $this->assertEqual($feeds[2]->language()->getId(), $this->langcodes[2]->getId());
 
     // Create example nodes to create feed items from and then update the feeds.
     $this->createSampleNodes();
diff -u b/core/modules/config/lib/Drupal/config/Tests/ConfigEntityTest.php b/core/modules/config/lib/Drupal/config/Tests/ConfigEntityTest.php
--- b/core/modules/config/lib/Drupal/config/Tests/ConfigEntityTest.php
+++ b/core/modules/config/lib/Drupal/config/Tests/ConfigEntityTest.php
@@ -43,7 +43,7 @@
    * Tests CRUD operations.
    */
   function testCRUD() {
-    $default_langcode = \Drupal::languageManager()->getDefaultLanguage()->id;
+    $default_langcode = \Drupal::languageManager()->getDefaultLanguage()->getId();
     // Verify default properties on a newly created empty entity.
     $empty = entity_create('config_test');
     $this->assertIdentical($empty->id, NULL);
diff -u b/core/modules/language/language.module b/core/modules/language/language.module
--- b/core/modules/language/language.module
+++ b/core/modules/language/language.module
@@ -427,13 +427,13 @@
   $language->is_new = $language_entity->isNew();
 
   // Assign language properties to language entity.
-  $language_entity->label = isset($language->name) ? $language->name : '';
-  $language_entity->direction = isset($language->direction) ? $language->direction : '0';
-  $language_entity->locked = !empty($language->locked);
-  $language_entity->weight = isset($language->weight) ? $language->weight : 0;
+  $language_entity->label = $language->getName();
+  $language_entity->direction = $language->getDirection();
+  $language_entity->locked = $language->isLocked();
+  $language_entity->weight = $language->getWeight();
   $language_entity->setDefault($language->isDefault());
   $language_entity->save();
-  $t_args = array('%language' => $language->name, '%langcode' => $language->getId());
+  $t_args = array('%language' => $language->getName(), '%langcode' => $language->getId());
   if ($language_entity->isNew()) {
     watchdog('language', 'The %language (%langcode) language has been created.', $t_args);
   }
diff -u b/core/modules/language/lib/Drupal/language/ConfigurableLanguageManager.php b/core/modules/language/lib/Drupal/language/ConfigurableLanguageManager.php
--- b/core/modules/language/lib/Drupal/language/ConfigurableLanguageManager.php
+++ b/core/modules/language/lib/Drupal/language/ConfigurableLanguageManager.php
@@ -291,14 +291,14 @@
         $data['default'] = ($langcode == $default->getId());
         $data['name'] = $data['label'];
         $this->languages[$langcode] = new Language($data);
-        $weight = max(array($weight, $this->languages[$langcode]->weight));
+        $weight = max(array($weight, $this->languages[$langcode]->getWeight()));
       }
 
       // Add locked languages, they will be filtered later if needed.
       $this->languages += $this->getDefaultLockedLanguages($weight);
 
       // Sort the language list by weight then title.
-      LanguageInterface::sort($this->languages);
+      uasort($this->languages, '\Drupal\Core\Language\Language::sort');
     }
 
     return parent::getLanguages($flags);
diff -u b/core/modules/language/lib/Drupal/language/LanguageNegotiatorInterface.php b/core/modules/language/lib/Drupal/language/LanguageNegotiatorInterface.php
--- b/core/modules/language/lib/Drupal/language/LanguageNegotiatorInterface.php
+++ b/core/modules/language/lib/Drupal/language/LanguageNegotiatorInterface.php
@@ -91,7 +91,7 @@
  *       // If we are on an administrative path, override with the default
  *       language.
  *       if ($request->query->has('q') && strtok($request->query->get('q'), '/') == 'admin') {
- *         return $this->languageManager->getDefaultLanguage()->id;
+ *         return $this->languageManager->getDefaultLanguage()->getId();
  *       }
  *       return $langcode;
  *     }
diff -u b/core/modules/language/lib/Drupal/language/Plugin/LanguageNegotiation/LanguageNegotiationUrl.php b/core/modules/language/lib/Drupal/language/Plugin/LanguageNegotiation/LanguageNegotiationUrl.php
--- b/core/modules/language/lib/Drupal/language/Plugin/LanguageNegotiation/LanguageNegotiationUrl.php
+++ b/core/modules/language/lib/Drupal/language/Plugin/LanguageNegotiation/LanguageNegotiationUrl.php
@@ -62,14 +62,14 @@
           // Search prefix within enabled languages.
           $negotiated_language = FALSE;
           foreach ($languages as $language) {
-            if (isset($config['prefixes'][$language->id]) && $config['prefixes'][$language->id] == $prefix) {
+            if (isset($config['prefixes'][$language->getId()]) && $config['prefixes'][$language->getId()] == $prefix) {
               $negotiated_language = $language;
               break;
             }
           }
 
           if ($negotiated_language) {
-            $langcode = $negotiated_language->id;
+            $langcode = $negotiated_language->getId();
           }
           break;
 
@@ -78,13 +78,13 @@
           $http_host = $request->getHost();
           foreach ($languages as $language) {
             // Skip the check if the language doesn't have a domain.
-            if (!empty($config['domains'][$language->id])) {
+            if (!empty($config['domains'][$language->getId()])) {
               // Ensure that there is exactly one protocol in the URL when
               // checking the hostname.
-              $host = 'http://' . str_replace(array('http://', 'https://'), '', $config['domains'][$language->id]);
+              $host = 'http://' . str_replace(array('http://', 'https://'), '', $config['domains'][$language->getId()]);
               $host = parse_url($host, PHP_URL_HOST);
               if ($http_host == $host) {
-                $langcode = $language->id;
+                $langcode = $language->getId();
                 break;
               }
             }
@@ -133,7 +133,7 @@
       $options['language'] = $language_url;
     }
     // We allow only enabled languages here.
-    elseif (!is_object($options['language']) || !isset($languages[$options['language']->id])) {
+    elseif (!is_object($options['language']) || !isset($languages[$options['language']->getId()])) {
       return $path;
     }
     $config = $this->config->get('language.negotiation')->get('url');
diff -u b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityFieldTest.php b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityFieldTest.php
--- b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityFieldTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Entity/EntityFieldTest.php
@@ -193,14 +193,14 @@
     $this->assertEqual(\Drupal::languageManager()->getLanguage(LanguageInterface::LANGCODE_NOT_SPECIFIED), $entity->langcode->language, format_string('%entity_type: Language object can be read.', array('%entity_type' => $entity_type)));
 
     // Change the language by code.
-    $entity->langcode->value = \Drupal::languageManager()->getDefaultLanguage()->id;
-    $this->assertEqual(\Drupal::languageManager()->getDefaultLanguage()->id, $entity->langcode->value, format_string('%entity_type: Language code can be read.', array('%entity_type' => $entity_type)));
+    $entity->langcode->value = \Drupal::languageManager()->getDefaultLanguage()->getId();
+    $this->assertEqual(\Drupal::languageManager()->getDefaultLanguage()->getId(), $entity->langcode->value, format_string('%entity_type: Language code can be read.', array('%entity_type' => $entity_type)));
     $this->assertEqual(\Drupal::languageManager()->getDefaultLanguage(), $entity->langcode->language, format_string('%entity_type: Language object can be read.', array('%entity_type' => $entity_type)));
 
     // Revert language by code then try setting it by language object.
     $entity->langcode->value = LanguageInterface::LANGCODE_NOT_SPECIFIED;
     $entity->langcode->language = \Drupal::languageManager()->getDefaultLanguage();
-    $this->assertEqual(\Drupal::languageManager()->getDefaultLanguage()->id, $entity->langcode->value, format_string('%entity_type: Language code can be read.', array('%entity_type' => $entity_type)));
+    $this->assertEqual(\Drupal::languageManager()->getDefaultLanguage()->getId(), $entity->langcode->value, format_string('%entity_type: Language code can be read.', array('%entity_type' => $entity_type)));
     $this->assertEqual(\Drupal::languageManager()->getDefaultLanguage(), $entity->langcode->language, format_string('%entity_type: Language object can be read.', array('%entity_type' => $entity_type)));
 
     // Access the text field and test updating.
diff -u b/core/modules/user/lib/Drupal/user/Plugin/LanguageNegotiation/LanguageNegotiationUserAdmin.php b/core/modules/user/lib/Drupal/user/Plugin/LanguageNegotiation/LanguageNegotiationUserAdmin.php
--- b/core/modules/user/lib/Drupal/user/Plugin/LanguageNegotiation/LanguageNegotiationUserAdmin.php
+++ b/core/modules/user/lib/Drupal/user/Plugin/LanguageNegotiation/LanguageNegotiationUserAdmin.php
@@ -82,7 +82,7 @@
     // User preference (only for authenticated users).
     if ($this->languageManager && $this->currentUser->isAuthenticated() && $this->isAdminPath($request)) {
       $preferred_admin_langcode = $this->currentUser->getPreferredAdminLangcode();
-      $default_langcode = $this->languageManager->getDefaultLanguage()->id;
+      $default_langcode = $this->languageManager->getDefaultLanguage()->getId();
       $languages = $this->languageManager->getLanguages();
       if (!empty($preferred_admin_langcode) && $preferred_admin_langcode != $default_langcode && isset($languages[$preferred_admin_langcode])) {
         $langcode = $preferred_admin_langcode;
diff -u b/core/modules/user/lib/Drupal/user/Tests/UserRegistrationTest.php b/core/modules/user/lib/Drupal/user/Tests/UserRegistrationTest.php
--- b/core/modules/user/lib/Drupal/user/Tests/UserRegistrationTest.php
+++ b/core/modules/user/lib/Drupal/user/Tests/UserRegistrationTest.php
@@ -185,8 +185,8 @@
     $this->assertTrue(($new_user->getCreatedTime() > REQUEST_TIME - 20 ), 'Correct creation time.');
     $this->assertEqual($new_user->isActive(), $config_user_settings->get('register') == USER_REGISTER_VISITORS ? 1 : 0, 'Correct status field.');
     $this->assertEqual($new_user->getTimezone(), $config_system_date->get('timezone.default'), 'Correct time zone field.');
-    $this->assertEqual($new_user->langcode->value, \Drupal::languageManager()->getDefaultLanguage()->id, 'Correct language field.');
-    $this->assertEqual($new_user->preferred_langcode->value, \Drupal::languageManager()->getDefaultLanguage()->id, 'Correct preferred language field.');
+    $this->assertEqual($new_user->langcode->value, \Drupal::languageManager()->getDefaultLanguage()->getId(), 'Correct language field.');
+    $this->assertEqual($new_user->preferred_langcode->value, \Drupal::languageManager()->getDefaultLanguage()->getId(), 'Correct preferred language field.');
     $this->assertEqual($new_user->init->value, $mail, 'Correct init field.');
   }
 
only in patch2:
unchanged:
--- a/core/modules/block/custom_block/lib/Drupal/custom_block/Tests/CustomBlockTypeTest.php
+++ b/core/modules/block/custom_block/lib/Drupal/custom_block/Tests/CustomBlockTypeTest.php
@@ -66,7 +66,7 @@ public function testCustomBlockTypeCreation() {
     $this->assertTrue($block_type, 'The new block type has been created.');
 
     // Check that the block type was created in site default language.
-    $default_langcode = \Drupal::languageManager()->getDefaultLanguage()->id;
+    $default_langcode = \Drupal::languageManager()->getDefaultLanguage()->getId();
     $this->assertEqual($block_type->langcode, $default_langcode);
   }
 
only in patch2:
unchanged:
--- a/core/modules/block/lib/Drupal/block/Tests/BlockStorageUnitTest.php
+++ b/core/modules/block/lib/Drupal/block/Tests/BlockStorageUnitTest.php
@@ -93,7 +93,7 @@ protected function createTests() {
       'id' => 'test_block',
       'weight' => NULL,
       'status' => TRUE,
-      'langcode' => \Drupal::languageManager()->getDefaultLanguage()->id,
+      'langcode' => \Drupal::languageManager()->getDefaultLanguage()->getId(),
       'dependencies' => array('module' => array('block_test'), 'theme' => array('stark')),
       'theme' => 'stark',
       'region' => '-1',
only in patch2:
unchanged:
--- a/core/modules/config/lib/Drupal/config/Tests/ConfigImportUITest.php
+++ b/core/modules/config/lib/Drupal/config/Tests/ConfigImportUITest.php
@@ -63,7 +63,7 @@ function testImport() {
       'test_dependencies' => array(),
       'status' => TRUE,
       'uuid' => '30df59bd-7b03-4cf7-bb35-d42fc49f0651',
-      'langcode' => \Drupal::languageManager()->getDefaultLanguage()->id,
+      'langcode' => \Drupal::languageManager()->getDefaultLanguage()->getId(),
       'dependencies' => array(),
       'protected_property' => '',
     );
only in patch2:
unchanged:
--- a/core/modules/config/lib/Drupal/config/Tests/ConfigImporterTest.php
+++ b/core/modules/config/lib/Drupal/config/Tests/ConfigImporterTest.php
@@ -178,7 +178,7 @@ function testNew() {
       'test_dependencies' => array(),
       'status' => TRUE,
       'uuid' => '30df59bd-7b03-4cf7-bb35-d42fc49f0651',
-      'langcode' => \Drupal::languageManager()->getDefaultLanguage()->id,
+      'langcode' => \Drupal::languageManager()->getDefaultLanguage()->getId(),
       'dependencies' => array(),
       'protected_property' => '',
     );
only in patch2:
unchanged:
--- a/core/modules/contact/lib/Drupal/contact/Tests/ContactSitewideTest.php
+++ b/core/modules/contact/lib/Drupal/contact/Tests/ContactSitewideTest.php
@@ -124,7 +124,7 @@ function testSiteWideContact() {
 
     // Check that the category was created in site default language.
     $langcode = \Drupal::config('contact.category.' . $id)->get('langcode');
-    $default_langcode = \Drupal::languageManager()->getDefaultLanguage()->id;
+    $default_langcode = \Drupal::languageManager()->getDefaultLanguage()->getId();
     $this->assertEqual($langcode, $default_langcode);
 
     // Make sure the newly created category is included in the list of categories.
only in patch2:
unchanged:
--- a/core/modules/filter/lib/Drupal/filter/Tests/FilterCrudTest.php
+++ b/core/modules/filter/lib/Drupal/filter/Tests/FilterCrudTest.php
@@ -84,7 +84,7 @@ function testTextFormatCrud() {
    */
   function verifyTextFormat($format) {
     $t_args = array('%format' => $format->name);
-    $default_langcode = \Drupal::languageManager()->getDefaultLanguage()->id;
+    $default_langcode = \Drupal::languageManager()->getDefaultLanguage()->getId();
 
     // Verify the loaded filter has all properties.
     $filter_format = entity_load('filter_format', $format->format);
only in patch2:
unchanged:
--- a/core/modules/forum/lib/Drupal/forum/Tests/ForumTest.php
+++ b/core/modules/forum/lib/Drupal/forum/Tests/ForumTest.php
@@ -300,7 +300,7 @@ private function doAdminTests($user) {
       'name' => 'Tags',
       'description' => $description,
       'vid' => 'tags',
-      'langcode' => \Drupal::languageManager()->getDefaultLanguage()->id,
+      'langcode' => \Drupal::languageManager()->getDefaultLanguage()->getId(),
       'help' => $help,
     ));
     $vocabulary->save();
only in patch2:
unchanged:
--- a/core/modules/forum/lib/Drupal/forum/Tests/ForumUninstallTest.php
+++ b/core/modules/forum/lib/Drupal/forum/Tests/ForumUninstallTest.php
@@ -42,7 +42,7 @@ function testForumUninstallWithField() {
     // Create a taxonomy term.
     $term = entity_create('taxonomy_term', array(
       'name' => t('A term'),
-      'langcode' => \Drupal::languageManager()->getDefaultLanguage()->id,
+      'langcode' => \Drupal::languageManager()->getDefaultLanguage()->getId(),
       'description' => '',
       'parent' => array(0),
       'vid' => 'forums',
only in patch2:
unchanged:
--- a/core/modules/language/lib/Drupal/language/Tests/LanguagePathMonolingualTest.php
+++ b/core/modules/language/lib/Drupal/language/Tests/LanguagePathMonolingualTest.php
@@ -57,7 +57,7 @@ function setUp() {
     // Verify that French is the only language.
     $this->container->get('language_manager')->reset();
     $this->assertFalse(\Drupal::languageManager()->isMultilingual(), 'Site is mono-lingual');
-    $this->assertEqual(\Drupal::languageManager()->getDefaultLanguage()->id, 'fr', 'French is the default language');
+    $this->assertEqual(\Drupal::languageManager()->getDefaultLanguage()->getId(), 'fr', 'French is the default language');
 
     // Set language detection to URL.
     $edit = array('language_interface[enabled][language-url]' => TRUE);
only in patch2:
unchanged:
--- a/core/modules/language/tests/Drupal/language/Tests/LanguageNegotiationUrlTest.php
+++ b/core/modules/language/tests/Drupal/language/Tests/LanguageNegotiationUrlTest.php
@@ -38,13 +38,17 @@ public static function getInfo() {
   public function setUp() {
 
     // Set up some languages to be used by the language-based path processor.
+    $language_de = $this->getMock('\Drupal\Core\Language\LanguageInterface');
+    $language_de->expects($this->any())
+      ->method('getId')
+      ->will($this->returnValue('de'));
+    $language_en = $this->getMock('\Drupal\Core\Language\LanguageInterface');
+    $language_en->expects($this->any())
+      ->method('getId')
+      ->will($this->returnValue('en'));
     $languages = array(
-      'de' => (object) array(
-        'id' => 'de',
-      ),
-      'en' => (object) array(
-        'id' => 'en',
-      ),
+      'de' => $language_de,
+      'en' => $language_en,
     );
 
     // Create a language manager stub.
only in patch2:
unchanged:
--- a/core/modules/user/lib/Drupal/user/Plugin/LanguageNegotiation/LanguageNegotiationUser.php
+++ b/core/modules/user/lib/Drupal/user/Plugin/LanguageNegotiation/LanguageNegotiationUser.php
@@ -36,7 +36,7 @@ public function getLangcode(Request $request = NULL) {
     // User preference (only for authenticated users).
     if ($this->languageManager && $this->currentUser->isAuthenticated()) {
       $preferred_langcode = $this->currentUser->getPreferredLangcode();
-      $default_langcode = $this->languageManager->getDefaultLanguage()->id;
+      $default_langcode = $this->languageManager->getDefaultLanguage()->getId();
       $languages = $this->languageManager->getLanguages();
       if (!empty($preferred_langcode) && $preferred_langcode != $default_langcode && isset($languages[$preferred_langcode])) {
         $langcode = $preferred_langcode;
only in patch2:
unchanged:
--- a/core/modules/user/lib/Drupal/user/Tests/UserInstallTest.php
+++ b/core/modules/user/lib/Drupal/user/Tests/UserInstallTest.php
@@ -51,8 +51,8 @@ public function testUserInstall() {
     $this->assertFalse(empty($anon->uuid), 'Anon user has a UUID');
     $this->assertFalse(empty($admin->uuid), 'Admin user has a UUID');
 
-    $this->assertEqual($anon->langcode, \Drupal::languageManager()->getDefaultLanguage()->id, 'Anon user language is the default.');
-    $this->assertEqual($admin->langcode, \Drupal::languageManager()->getDefaultLanguage()->id, 'Admin user language is the default.');
+    $this->assertEqual($anon->langcode, \Drupal::languageManager()->getDefaultLanguage()->getId(), 'Anon user language is the default.');
+    $this->assertEqual($admin->langcode, \Drupal::languageManager()->getDefaultLanguage()->getId(), 'Admin user language is the default.');
 
     $this->assertEqual($admin->status, 1, 'Admin user is active.');
     $this->assertEqual($anon->status, 0, 'Anon user is blocked.');
only in patch2:
unchanged:
--- a/core/modules/user/lib/Drupal/user/Tests/UserRoleAdminTest.php
+++ b/core/modules/user/lib/Drupal/user/Tests/UserRoleAdminTest.php
@@ -32,7 +32,7 @@ function setUp() {
    */
   function testRoleAdministration() {
     $this->drupalLogin($this->admin_user);
-    $default_langcode = \Drupal::languageManager()->getDefaultLanguage()->id;
+    $default_langcode = \Drupal::languageManager()->getDefaultLanguage()->getId();
     // Test presence of tab.
     $this->drupalGet('admin/people/permissions');
     $tabs = $this->xpath('//ul[@class=:classes and //a[contains(., :text)]]', array(
only in patch2:
unchanged:
--- a/core/modules/user/user.module
+++ b/core/modules/user/user.module
@@ -1474,7 +1474,7 @@ function _user_mail_notify($op, $account, $langcode = NULL) {
     if ($op == 'register_pending_approval') {
       // If a user registered requiring admin approval, notify the admin, too.
       // We use the site default language for this.
-      drupal_mail('user', 'register_pending_approval_admin', $site_mail, \Drupal::languageManager()->getDefaultLanguage()->id, $params);
+      drupal_mail('user', 'register_pending_approval_admin', $site_mail, \Drupal::languageManager()->getDefaultLanguage()->getId(), $params);
     }
   }
   return empty($mail) ? NULL : $mail['result'];
only in patch2:
unchanged:
--- a/core/modules/views/lib/Drupal/views/Tests/Entity/RowEntityRenderersTest.php
+++ b/core/modules/views/lib/Drupal/views/Tests/Entity/RowEntityRenderersTest.php
@@ -63,7 +63,7 @@ protected function setUp() {
     // The node.view route must exist when nodes are rendered.
     $this->container->get('router.builder')->rebuild();
 
-    $this->langcodes = array(\Drupal::languageManager()->getDefaultLanguage()->id);
+    $this->langcodes = array(\Drupal::languageManager()->getDefaultLanguage()->getId());
     for ($i = 0; $i < 2; $i++) {
       $langcode = 'l' . $i;
       $this->langcodes[] = $langcode;