diff --git a/core/lib/Drupal/Core/DependencyInjection/YamlFileLoader.php b/core/lib/Drupal/Core/DependencyInjection/YamlFileLoader.php
index a2ef204..60f2809 100644
--- a/core/lib/Drupal/Core/DependencyInjection/YamlFileLoader.php
+++ b/core/lib/Drupal/Core/DependencyInjection/YamlFileLoader.php
@@ -33,13 +33,20 @@ class YamlFileLoader {
   static protected $yaml = array();
 
   /**
+   * The YAML parser.
+   *
+   * @var \Drupal\Component\Yaml\Yaml
+   */
+  protected $parser;
+
+  /**
    * @param \Drupal\Core\DependencyInjection\ContainerBuilder $container
    */
   protected $container;
 
   public function __construct(ContainerBuilder $container) {
     $this->container = $container;
-    $this->yaml = new Yaml();
+    $this->parser = new Yaml();
   }
 
   /**
@@ -191,7 +198,7 @@ protected function parseDefinition($id, $service, $filename) {
    *   The file content.
    */
   protected function loadFile($filename) {
-    return $this->validate($this->yaml->parse(file_get_contents($filename)), $filename);
+    return $this->validate($this->parser->parse(file_get_contents($filename)), $filename);
   }
 
   /**