Drupal 8.0.0 beta 12. More info: https://www.drupal.org/node/2514176

core/modules/file/templates/file-managed-file.html.twig

@@ -0,0 +1,23 @@
+{#
+/**
+ * @file
+ * Default theme implementation to display a file form widget.
+ *
+ * Available variables:
+ * - element: Form element for the file upload.
+ * - attributes: HTML attributes for the containing element.
+ *
+ * @see template_preprocess_file_managed_file()
+ *
+ * @ingroup themeable
+ */
+#}
+{%
+  set classes = [
+    'js-form-managed-file',
+    'form-managed-file',
+  ]
+%}
+<div{{ attributes.addClass(classes) }}>
+  {{ element }}
+</div>