diff -r 000000000000 -r 6474c204b198 layout/xul/nsISliderListener.idl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/layout/xul/nsISliderListener.idl	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,26 @@
+/* -*- Mode: C++; 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 "nsISupports.idl"
+
+/**
+ * Used for <scale> to listen to slider changes to avoid mutation listeners
+ */
+[scriptable, uuid(e5b3074e-ee18-4538-83b9-2487d90a2a34)]
+interface nsISliderListener : nsISupports
+{
+  /**
+   * Called when the current, minimum or maximum value has been changed to
+   * newValue. The which parameter will either be 'curpos', 'minpos' or 'maxpos'.
+   * If userChanged is true, then the user changed ths slider, otherwise it
+   * was changed via some other means.
+   */
+  void valueChanged(in AString which, in long newValue, in boolean userChanged);
+
+  /**
+   * Called when the user begins or ends dragging the thumb.
+   */
+  void dragStateChanged(in boolean isDragging);
+};