Distinct field building and adding action for ListBuilder.

Builder/ListBuilder.php

@@ -46,7 +46,7 @@ class ListBuilder implements ListBuilderInterface
     /**
      * {@inheritdoc}
      */
-    public function addField(FieldDescriptionCollection $list, $type = null, FieldDescriptionInterface $fieldDescription, AdminInterface $admin)
+    public function buildField($type = null, FieldDescriptionInterface $fieldDescription, AdminInterface $admin)
     {
         if ($type == null) {
             $guessType = $this->guesser->guessType($admin->getClass(), $fieldDescription->getName(), $admin->getModelManager());
@@ -56,6 +56,14 @@ class ListBuilder implements ListBuilderInterface
         }
 
         $this->fixFieldDescription($admin, $fieldDescription);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function addField(FieldDescriptionCollection $list, $type = null, FieldDescriptionInterface $fieldDescription, AdminInterface $admin)
+    {
+        $this->buildField($type, $fieldDescription, $admin);
         $admin->addListFieldDescription($fieldDescription->getName(), $fieldDescription);
 
         return $list->add($fieldDescription);