diff -r 000000000000 -r 6474c204b198 dom/interfaces/html/nsIDOMHTMLCollection.idl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/interfaces/html/nsIDOMHTMLCollection.idl	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,26 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "domstubs.idl"
+
+/**
+ * The nsIDOMHTMLCollection interface is an interface to a collection
+ * of [X]HTML elements.
+ *
+ * This interface is trying to follow the DOM Level 2 HTML specification:
+ * http://www.w3.org/TR/DOM-Level-2-HTML/
+ *
+ * with changes from the work-in-progress WHATWG HTML specification:
+ * http://www.whatwg.org/specs/web-apps/current-work/
+ */
+
+[scriptable, uuid(bb07f567-5b37-4172-92aa-7d00ceed4809)]
+interface nsIDOMHTMLCollection : nsISupports
+{
+  readonly attribute unsigned long    length;
+
+  nsIDOMNode item(in unsigned long index);
+  nsIDOMNode namedItem(in DOMString name);
+};