diff -r 000000000000 -r 6474c204b198 dom/webidl/CSSStyleDeclaration.webidl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/webidl/CSSStyleDeclaration.webidl	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,37 @@
+/* -*- 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/.
+ *
+ * The origin of this IDL file is
+ * http://dev.w3.org/csswg/cssom/
+ */
+
+interface CSSRule;
+
+interface CSSStyleDeclaration {
+  [SetterThrows]
+  attribute DOMString cssText;
+
+  readonly attribute unsigned long length;
+  getter DOMString item(unsigned long index);
+
+  [Throws]
+  DOMString getPropertyValue(DOMString property);
+  // Mozilla extension, sort of
+  [Throws]
+  CSSValue? getPropertyCSSValue(DOMString property);
+  DOMString getPropertyPriority(DOMString property);
+  [Throws]
+  void setProperty(DOMString property, DOMString value, [TreatNullAs=EmptyString] optional DOMString priority = "");
+  [Throws]
+  DOMString removeProperty(DOMString property);
+
+  readonly attribute CSSRule? parentRule;
+};
+
+// Mozilla extensions
+partial interface CSSStyleDeclaration {
+  [ChromeOnly,Throws]
+  DOMString getAuthoredPropertyValue(DOMString property);
+};