diff --git a/core/lib/Drupal/Core/Config/DatabaseStorage.php b/core/lib/Drupal/Core/Config/DatabaseStorage.php
index ad5a645..4e0c184 100644
--- a/core/lib/Drupal/Core/Config/DatabaseStorage.php
+++ b/core/lib/Drupal/Core/Config/DatabaseStorage.php
@@ -181,7 +181,7 @@ protected function ensureTableExists()  {
   /**
    * Defines the schema for the configuration table.
    */
-  public static function schemaDefinition() {
+  protected static function schemaDefinition() {
     $schema = array(
       'description' => 'The base table for configuration data.',
       'fields' => array(