diff -r 000000000000 -r 6474c204b198 widget/gtk/nsScreenGtk.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/gtk/nsScreenGtk.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,49 @@
+/* -*- 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/. */
+
+#ifndef nsScreenGtk_h___
+#define nsScreenGtk_h___
+
+#include "nsBaseScreen.h"
+#include "nsRect.h"
+#include "gdk/gdk.h"
+#ifdef MOZ_X11
+#include <X11/Xlib.h>
+
+// from Xinerama.h
+typedef struct {
+   int   screen_number;
+   short x_org;
+   short y_org;
+   short width;
+   short height;
+} XineramaScreenInfo;
+#endif /* MOZ_X11 */
+
+//------------------------------------------------------------------------
+
+class nsScreenGtk : public nsBaseScreen
+{
+public:
+  nsScreenGtk();
+  ~nsScreenGtk();
+
+  NS_IMETHOD GetRect(int32_t* aLeft, int32_t* aTop, int32_t* aWidth, int32_t* aHeight);
+  NS_IMETHOD GetAvailRect(int32_t* aLeft, int32_t* aTop, int32_t* aWidth, int32_t* aHeight);
+  NS_IMETHOD GetPixelDepth(int32_t* aPixelDepth);
+  NS_IMETHOD GetColorDepth(int32_t* aColorDepth);
+
+  void Init(GdkWindow *aRootWindow);
+#ifdef MOZ_X11
+  void Init(XineramaScreenInfo *aScreenInfo);
+#endif /* MOZ_X11 */
+
+private:
+  uint32_t mScreenNum;
+  nsIntRect mRect;
+  nsIntRect mAvailRect;
+};
+
+#endif  // nsScreenGtk_h___