diff --git a/core/lib/Drupal/Core/Config/TypedConfigManager.php b/core/lib/Drupal/Core/Config/TypedConfigManager.php
index 108bd8e..b4d454a 100644
--- a/core/lib/Drupal/Core/Config/TypedConfigManager.php
+++ b/core/lib/Drupal/Core/Config/TypedConfigManager.php
@@ -106,7 +106,11 @@ public function create(array $definition, $value = NULL, $name = NULL, $parent =
     // Create typed config object.
     $definition['name'] = $name;
     $definition['parent'] = $parent;
-    $wrapper = $this->createInstance($definition['type'], $definition);
+    $wrapper = $this->createInstance($definition['type'], array(
+      'data_definition' => $definition,
+      'name' => $name,
+      'parent' => $parent,
+    ));
     if (isset($value)) {
       $wrapper->setValue($value, FALSE);
     }
@@ -117,17 +121,20 @@ public function create(array $definition, $value = NULL, $name = NULL, $parent =
    * {@inheritdoc}
    */
   public function createInstance($data_type, array $configuration = array()) {
+    $data_definition = $configuration['data_definition'];
     $type_definition = $this->getDefinition($data_type);
+
     if (!isset($type_definition)) {
       throw new \InvalidArgumentException(String::format('Invalid data type %plugin_id has been given.', array('%plugin_id' => $data_type)));
     }
 
-    $configuration += $type_definition;
     // Allow per-data definition overrides of the used classes, i.e. take over
-    // classes specified in the data definition.
-    $key = empty($configuration['list']) ? 'class' : 'list class';
-    if (isset($configuration[$key])) {
-      $class = $configuration[$key];
+    // classes specified in the type definition.
+    $data_definition += $type_definition;
+
+    $key = empty($data_definition['list']) ? 'class' : 'list class';
+    if (isset($data_definition[$key])) {
+      $class = $data_definition[$key];
     }
     elseif (isset($type_definition[$key])) {
       $class = $type_definition[$key];
@@ -136,7 +143,7 @@ public function createInstance($data_type, array $configuration = array()) {
     if (!isset($class)) {
       throw new PluginException(sprintf('The plugin (%s) did not specify an instance class.', $data_type));
     }
-    return new $class($configuration, $configuration['name'], $configuration['parent']);
+    return new $class($data_definition, $configuration['name'], $configuration['parent']);
   }
 
   /**