diff --git a/core/lib/Drupal/Core/Cache/CacheCollector.php b/core/lib/Drupal/Core/Cache/CacheCollector.php
index bbfd77e..28c9026 100644
--- a/core/lib/Drupal/Core/Cache/CacheCollector.php
+++ b/core/lib/Drupal/Core/Cache/CacheCollector.php
@@ -209,9 +209,18 @@ protected function updateCache($lock = TRUE) {
   }
 
   /**
-   * Implemnts KernelServiceTerminator::terminate().
+   * Implements KernelServiceTerminator::terminate().
    */
   public function terminate() {
     $this->updateCache();
   }
+
+  /**
+   * Implements CacheCollectorInterface::reset().
+   */
+  public function reset() {
+    $this->storage = array();
+    $this->keysToPersist = array();
+    $this->keysToRemove = array();
+  }
 }
diff --git a/core/lib/Drupal/Core/Cache/CacheCollectorInterface.php b/core/lib/Drupal/Core/Cache/CacheCollectorInterface.php
index be9385f..f54f1d7 100644
--- a/core/lib/Drupal/Core/Cache/CacheCollectorInterface.php
+++ b/core/lib/Drupal/Core/Cache/CacheCollectorInterface.php
@@ -64,4 +64,10 @@ public function delete($key);
    *   Key that identifies the data.
    */
   public function has($key);
+
+  /**
+   * Resets the local cache.
+   */
+  public function reset();
+
 }
diff --git a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
index f886992..ce9ba3e 100644
--- a/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
+++ b/core/modules/simpletest/lib/Drupal/simpletest/WebTestBase.php
@@ -899,6 +899,7 @@ protected function refreshVariables() {
     cache('bootstrap')->delete('variables');
     $conf = variable_initialize();
     drupal_container()->get('config.factory')->reset();
+    drupal_container()->get('state')->reset();
   }
 
   /**