diff -r 000000000000 -r 6474c204b198 dom/interfaces/css/nsIDOMCSSConditionRule.idl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/interfaces/css/nsIDOMCSSConditionRule.idl	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,16 @@
+/* -*- 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 "nsIDOMCSSGroupingRule.idl"
+
+/**
+ * Interface in the CSS OM for at-rules that conditionally apply their
+ * child rules.
+ */
+[scriptable, uuid(942754f2-2c0e-461b-9c10-c0e929504fe1)]
+interface nsIDOMCSSConditionRule : nsIDOMCSSGroupingRule
+{
+  attribute DOMString conditionText;
+};