Allow to get parent of BaseNode

src/Symfony/Component/Config/Definition/BaseNode.php

@@ -280,6 +280,16 @@ abstract class BaseNode implements NodeInterface
         return $value;
     }
 
+    /**
+     * Returns parent node for this node.
+     *
+     * @return NodeInterface|null
+     */
+    public function getParent()
+    {
+        return $this->parent;
+    }
+
     /**
      * Finalizes a value, applying all finalization closures.
      *