diff -r 000000000000 -r 6474c204b198 widget/windows/nsScreenWin.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/windows/nsScreenWin.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,39 @@
+/* -*- 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 nsScreenWin_h___
+#define nsScreenWin_h___
+
+#include <windows.h>
+#include "nsBaseScreen.h"
+
+//------------------------------------------------------------------------
+
+class nsScreenWin : public nsBaseScreen
+{
+public:
+  nsScreenWin ( HMONITOR inScreen );
+  ~nsScreenWin();
+
+  // These methods return the size in device (physical) pixels
+  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);
+
+  // And these methods get the screen size in 'display pixels' (AKA 'logical pixels')
+  // that are dependent on the logical DPI setting in windows
+  NS_IMETHOD GetRectDisplayPix(int32_t *outLeft,  int32_t *outTop,
+                               int32_t *outWidth, int32_t *outHeight);
+  NS_IMETHOD GetAvailRectDisplayPix(int32_t *outLeft,  int32_t *outTop,
+                                    int32_t *outWidth, int32_t *outHeight);
+
+  NS_IMETHOD GetPixelDepth(int32_t* aPixelDepth);
+  NS_IMETHOD GetColorDepth(int32_t* aColorDepth);
+
+private:
+
+  HMONITOR mScreen;
+};
+
+#endif  // nsScreenWin_h___