diff --git a/core/modules/language/lib/Drupal/language/Tests/LanguageListTest.php b/core/modules/language/lib/Drupal/language/Tests/LanguageListTest.php
index b05808d..6b0f130 100644
--- a/core/modules/language/lib/Drupal/language/Tests/LanguageListTest.php
+++ b/core/modules/language/lib/Drupal/language/Tests/LanguageListTest.php
@@ -111,6 +111,7 @@ function testLanguageList() {
     // Delete the language for real. This a confirm form, we do not need any
     // fields changed.
     $this->drupalPostForm('admin/config/regional/language/delete/' . $langcode, array(), t('Delete'));
+    \Drupal::state()->resetCache();
     // We need raw here because %language and %langcode will add HTML.
     $t_args = array('%language' => $name, '%langcode' => $langcode);
     $this->assertRaw(t('The %language (%langcode) language has been removed.', $t_args), 'The test language has been removed.');
@@ -152,6 +153,7 @@ function testLanguageList() {
       'direction' => '0',
     );
     $this->drupalPostForm('admin/config/regional/language/add', $edit, t('Add custom language'));
+    \Drupal::state()->resetCache();
     $this->assertEqual($this->getUrl(), url('admin/config/regional/language', array('absolute' => TRUE)), 'Correct page redirection.');
     $this->assertText($name, 'Name found.');
 
diff --git a/core/modules/rest/lib/Drupal/rest/Plugin/views/display/RestExport.php b/core/modules/rest/lib/Drupal/rest/Plugin/views/display/RestExport.php
index 19bc077..cef8953 100644
--- a/core/modules/rest/lib/Drupal/rest/Plugin/views/display/RestExport.php
+++ b/core/modules/rest/lib/Drupal/rest/Plugin/views/display/RestExport.php
@@ -8,7 +8,7 @@
 namespace Drupal\rest\Plugin\views\display;
 
 
-use Drupal\Core\KeyValueStore\KeyValueStoreInterface;
+use Drupal\Core\KeyValueStore\StateInterface;
 use Drupal\Core\Routing\RouteProviderInterface;
 use Drupal\views\Annotation\ViewsDisplay;
 use Drupal\Core\Annotation\Translation;
@@ -99,14 +99,14 @@ class RestExport extends PathPluginBase {
    *   The plugin implementation definition.
    * @param \Drupal\Core\Routing\RouteProviderInterface $route_provider
    *   The route provider
-   * @param \Drupal\Core\KeyValueStore\KeyValueStoreInterface $state
+   * @param \Drupal\Core\KeyValueStore\StateInterface $state
    *   The state key value store.
    * @param \Drupal\Core\ContentNegotiation $content_negotiation
    *   The content negotiation library.
    * @param \Symfony\Component\HttpFoundation\Request $request
    *   The request object.
    */
-  public function __construct(array $configuration, $plugin_id, array $plugin_definition, RouteProviderInterface $route_provider, KeyValueStoreInterface $state, ContentNegotiation $content_negotiation, Request $request) {
+  public function __construct(array $configuration, $plugin_id, array $plugin_definition, RouteProviderInterface $route_provider, StateInterface $state, ContentNegotiation $content_negotiation, Request $request) {
     parent::__construct($configuration, $plugin_id, $plugin_definition, $route_provider, $state);
     $this->contentNegotiation = $content_negotiation;
     $this->request = $request;
diff --git a/core/modules/rest/tests/Drupal/rest/Tests/CollectRoutesTest.php b/core/modules/rest/tests/Drupal/rest/Tests/CollectRoutesTest.php
index ae4bb43..05c6d5d 100644
--- a/core/modules/rest/tests/Drupal/rest/Tests/CollectRoutesTest.php
+++ b/core/modules/rest/tests/Drupal/rest/Tests/CollectRoutesTest.php
@@ -82,7 +82,7 @@ protected function setUp() {
       ->getMock();
     $container->set('router.route_provider', $route_provider);
 
-    $state = $this->getMock('\Drupal\Core\KeyValueStore\KeyValueStoreInterface');
+    $state = $this->getMock('\Drupal\Core\KeyValueStore\StateInterface');
     $container->set('state', $state);
 
     $style_manager = $this->getMockBuilder('\Drupal\views\Plugin\ViewsPluginManager')
diff --git a/core/modules/system/lib/Drupal/system/Tests/Batch/ProcessingTest.php b/core/modules/system/lib/Drupal/system/Tests/Batch/ProcessingTest.php
index 83c8671..0008e5f 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Batch/ProcessingTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Batch/ProcessingTest.php
@@ -99,6 +99,7 @@ function testBatchFormMultistep() {
     // Second step triggers batch 2.
     $this->drupalPostForm(NULL, array(), 'Submit');
     $this->assertBatchMessages($this->_resultMessages('batch_2'), 'Batch for step 2 performed successfully.');
+    \Drupal::state()->resetCache();
     $this->assertEqual(batch_test_stack(), $this->_resultStack('batch_2'), 'Execution order was correct.');
     $this->assertText('Redirection successful.', 'Redirection after batch execution is correct.');
   }
diff --git a/core/modules/system/tests/modules/menu_test/lib/Drupal/menu_test/EventSubscriber/ActiveTrailSubscriber.php b/core/modules/system/tests/modules/menu_test/lib/Drupal/menu_test/EventSubscriber/ActiveTrailSubscriber.php
index 4bb3595..5b63e55 100644
--- a/core/modules/system/tests/modules/menu_test/lib/Drupal/menu_test/EventSubscriber/ActiveTrailSubscriber.php
+++ b/core/modules/system/tests/modules/menu_test/lib/Drupal/menu_test/EventSubscriber/ActiveTrailSubscriber.php
@@ -7,7 +7,7 @@
 
 namespace Drupal\menu_test\EventSubscriber;
 
-use Drupal\Core\KeyValueStore\KeyValueStoreInterface;
+use Drupal\Core\KeyValueStore\StateInterface;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
 use Symfony\Component\HttpKernel\Event\GetResponseEvent;
 use Symfony\Component\HttpKernel\KernelEvents;
@@ -27,17 +27,17 @@ class ActiveTrailSubscriber implements EventSubscriberInterface {
   /**
    * The state service.
    *
-   * @var \Drupal\Core\KeyValueStore\KeyValueStoreInterface
+   * @var \Drupal\Core\KeyValueStore\StateInterface
    */
   protected $state;
 
   /**
    * Constructs a new ActiveTrailSubscriber.
    *
-   * @param \Drupal\Core\KeyValueStore\KeyValueStoreInterface $state
+   * @param \Drupal\Core\KeyValueStore\StateInterface $state
    *   The state service.
    */
-  public function __construct(KeyValueStoreInterface $state) {
+  public function __construct(StateInterface $state) {
     $this->state = $state;
   }
 
diff --git a/core/modules/views_ui/tests/Drupal/views_ui/Tests/ViewListControllerTest.php b/core/modules/views_ui/tests/Drupal/views_ui/Tests/ViewListControllerTest.php
index b30bb34..12a0984 100644
--- a/core/modules/views_ui/tests/Drupal/views_ui/Tests/ViewListControllerTest.php
+++ b/core/modules/views_ui/tests/Drupal/views_ui/Tests/ViewListControllerTest.php
@@ -77,7 +77,7 @@ public function testBuildRowEntityList() {
       array(array(), 'default', $display_manager->getDefinition('default'))
     );
     $route_provider = $this->getMock('Drupal\Core\Routing\RouteProviderInterface');
-    $state = $this->getMock('\Drupal\Core\KeyValueStore\KeyValueStoreInterface');
+    $state = $this->getMock('\Drupal\Core\KeyValueStore\StateInterface');
     $page_display = $this->getMock('Drupal\views\Plugin\views\display\Page',
       array('initDisplay', 'getPath'),
       array(array(), 'default', $display_manager->getDefinition('page'), $route_provider, $state)