diff -r 000000000000 -r 6474c204b198 widget/gtk/nsBidiKeyboard.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/gtk/nsBidiKeyboard.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,71 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim:expandtab:shiftwidth=4:tabstop=4:
+ */
+/* 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 "prlink.h"
+
+#include "nsBidiKeyboard.h"
+#include <gtk/gtk.h>
+
+#if (MOZ_WIDGET_GTK == 2)
+typedef gboolean (*GdkKeymapHaveBidiLayoutsType)(GdkKeymap *keymap);
+static GdkKeymapHaveBidiLayoutsType GdkKeymapHaveBidiLayouts = nullptr;
+#endif
+
+NS_IMPL_ISUPPORTS(nsBidiKeyboard, nsIBidiKeyboard)
+
+nsBidiKeyboard::nsBidiKeyboard()
+{
+    Reset();
+}
+
+NS_IMETHODIMP
+nsBidiKeyboard::Reset()
+{
+#if (MOZ_WIDGET_GTK == 2)
+    PRLibrary *gtklib = nullptr;
+#if defined(MOZ_X11)
+    if (!GdkKeymapHaveBidiLayouts) {
+        GdkKeymapHaveBidiLayouts = (GdkKeymapHaveBidiLayoutsType) 
+            PR_FindFunctionSymbolAndLibrary("gdk_keymap_have_bidi_layouts",
+                                            &gtklib);
+        if (gtklib)
+            PR_UnloadLibrary(gtklib);
+    }
+#endif
+
+    mHaveBidiKeyboards = false;
+    if (GdkKeymapHaveBidiLayouts)
+        mHaveBidiKeyboards = (*GdkKeymapHaveBidiLayouts)(nullptr);
+#else
+    mHaveBidiKeyboards = gdk_keymap_have_bidi_layouts(gdk_keymap_get_default());
+#endif
+    return NS_OK;
+}
+
+nsBidiKeyboard::~nsBidiKeyboard()
+{
+#if (MOZ_WIDGET_GTK == 2)
+    GdkKeymapHaveBidiLayouts = nullptr;
+#endif
+}
+
+NS_IMETHODIMP
+nsBidiKeyboard::IsLangRTL(bool *aIsRTL)
+{
+    if (!mHaveBidiKeyboards)
+        return NS_ERROR_FAILURE;
+
+    *aIsRTL = (gdk_keymap_get_direction(gdk_keymap_get_default()) == PANGO_DIRECTION_RTL);
+
+    return NS_OK;
+}
+
+NS_IMETHODIMP nsBidiKeyboard::GetHaveBidiKeyboards(bool* aResult)
+{
+  // not implemented yet
+  return NS_ERROR_NOT_IMPLEMENTED;
+}