diff --git a/core/modules/comment/lib/Drupal/comment/Tests/CommentLanguageTest.php b/core/modules/comment/lib/Drupal/comment/Tests/CommentLanguageTest.php
index a704fb7..474ae69 100644
--- a/core/modules/comment/lib/Drupal/comment/Tests/CommentLanguageTest.php
+++ b/core/modules/comment/lib/Drupal/comment/Tests/CommentLanguageTest.php
@@ -56,7 +56,7 @@ function setUp() {
     $this->drupalPost('admin/structure/types/manage/article', $edit, t('Save content type'));
 
     // Enable content language negotiation UI.
-    variable_set('language_test_content_language_type', TRUE);
+    state()->set('language_test.content_language_type', TRUE);
 
     // Set interface language detection to user and content language detection
     // to URL. Disable inheritance from interface language to ensure content
diff --git a/core/modules/language/lib/Drupal/language/Tests/LanguageNegotiationInfoTest.php b/core/modules/language/lib/Drupal/language/Tests/LanguageNegotiationInfoTest.php
index 961a556..436b371 100644
--- a/core/modules/language/lib/Drupal/language/Tests/LanguageNegotiationInfoTest.php
+++ b/core/modules/language/lib/Drupal/language/Tests/LanguageNegotiationInfoTest.php
@@ -42,8 +42,8 @@ function setUp() {
    */
   function testInfoAlterations() {
     // Enable language type/negotiation info alterations.
-    variable_set('language_test_language_types', TRUE);
-    variable_set('language_test_language_negotiation_info', TRUE);
+    state()->set('language_test.language_types', TRUE);
+    state()->set('language_test.language_negotiation_info', TRUE);
     $this->languageNegotiationUpdate();
 
     // Check that fixed language types are properly configured without the need
@@ -52,7 +52,7 @@ function testInfoAlterations() {
 
     // Make the content language type configurable by updating the language
     // negotiation settings with the proper flag enabled.
-    variable_set('language_test_content_language_type', TRUE);
+    state()->set('language_test.content_language_type', TRUE);
     $this->languageNegotiationUpdate();
     $type = LANGUAGE_TYPE_CONTENT;
     $language_types = variable_get('language_types', language_types_get_default());
@@ -73,7 +73,7 @@ function testInfoAlterations() {
 
     // Remove the interface language negotiation method by updating the language
     // negotiation settings with the proper flag enabled.
-    variable_set('language_test_language_negotiation_info_alter', TRUE);
+    state()->set('language_test.language_negotiation_info_alter', TRUE);
     $this->languageNegotiationUpdate();
     $negotiation = variable_get("language_negotiation_$type", array());
     $this->assertFalse(isset($negotiation[$interface_method_id]), 'Interface language negotiation method removed from the stored settings.');
@@ -93,7 +93,7 @@ function testInfoAlterations() {
 
     // Check language negotiation results.
     $this->drupalGet('');
-    $last = variable_get('language_test_language_negotiation_last', array());
+    $last = state()->get('language_test.language_negotiation_last');
     foreach (language_types_get_all() as $type) {
       $langcode = $last[$type];
       $value = $type == LANGUAGE_TYPE_CONTENT || strpos($type, 'test') !== FALSE ? 'it' : 'en';
diff --git a/core/modules/language/lib/Drupal/language/Tests/LanguageUILanguageNegotiationTest.php b/core/modules/language/lib/Drupal/language/Tests/LanguageUILanguageNegotiationTest.php
index 66e7007..18d23db 100644
--- a/core/modules/language/lib/Drupal/language/Tests/LanguageUILanguageNegotiationTest.php
+++ b/core/modules/language/lib/Drupal/language/Tests/LanguageUILanguageNegotiationTest.php
@@ -382,7 +382,7 @@ protected function runTest($test) {
         ->save();
     }
     if (!empty($test['language_test_domain'])) {
-      variable_set('language_test_domain', $test['language_test_domain']);
+      state()->set('language_test.domain', $test['language_test_domain']);
     }
     $this->drupalGet($test['path'], array(), $test['http_header']);
     $this->assertText($test['expect'], $test['message']);
diff --git a/core/modules/language/tests/language_test.module b/core/modules/language/tests/language_test.module
index be0a8c0..c15cc80 100644
--- a/core/modules/language/tests/language_test.module
+++ b/core/modules/language/tests/language_test.module
@@ -12,8 +12,8 @@
  * the HTTP_HOST here
  */
 function language_test_boot() {
-  if (variable_get('language_test_domain')) {
-    $_SERVER['HTTP_HOST'] = variable_get('language_test_domain');
+  if (state()->get('language_test.domain')) {
+    $_SERVER['HTTP_HOST'] = state()->get('language_test.domain');
   }
 }
 
@@ -31,7 +31,7 @@ function language_test_init() {
  * Implements hook_language_types_info().
  */
 function language_test_language_types_info() {
-  if (variable_get('language_test_language_types', FALSE)) {
+  if (state()->get('language_test.language_types')) {
     return array(
       'test_language_type' => array(
         'name' => t('Test'),
@@ -48,7 +48,7 @@ function language_test_language_types_info() {
  * Implements hook_language_types_info_alter().
  */
 function language_test_language_types_info_alter(array &$language_types) {
-  if (variable_get('language_test_content_language_type', FALSE)) {
+  if (state()->get('language_test.content_language_type')) {
     unset($language_types[LANGUAGE_TYPE_CONTENT]['fixed']);
   }
 }
@@ -57,7 +57,7 @@ function language_test_language_types_info_alter(array &$language_types) {
  * Implements hook_language_negotiation_info().
  */
 function language_test_language_negotiation_info() {
-  if (variable_get('language_test_language_negotiation_info', FALSE)) {
+  if (state()->get('language_test.language_negotiation_info')) {
     $info = array(
       'callbacks' => array(
         'negotiation' => 'language_test_language_negotiation_method',
@@ -84,7 +84,7 @@ function language_test_language_negotiation_info() {
  * Implements hook_language_negotiation_info_alter().
  */
 function language_test_language_negotiation_info_alter(array &$negotiation_info) {
-  if (variable_get('language_test_language_negotiation_info_alter', FALSE)) {
+  if (state()->get('language_test.language_negotiation_info_alter')) {
     unset($negotiation_info[LANGUAGE_NEGOTIATION_INTERFACE]);
   }
 }
@@ -97,7 +97,7 @@ function language_test_store_language_negotiation() {
   foreach (language_types_get_all() as $type) {
     $last[$type] = language($type)->langcode;
   }
-  variable_set('language_test_language_negotiation_last', $last);
+  state()->set('language_test.language_negotiation_last', $last);
 }
 
 /**