GDK W32: Don't move windows into top-left corner on style change

This fixes a bug that was introduced by db1b24233e.
The reason why 0:0 coordinates were passed was that SWP_NOREPOSITION was
misinterpreted as SWP_NOMOVE. That is not the case - SWP_NOREPOSITION
prevents owner Z-order change, not the window position change.

gdk/win32/gdkwindow-win32.c

@@ -2785,7 +2785,7 @@ _gdk_win32_window_update_style_bits (GdkWindow *window)
     }
 
   SetWindowPos (GDK_WINDOW_HWND (window), insert_after,
-		0, 0,
+		rect.left, rect.top,
 		rect.right - rect.left, rect.bottom - rect.top,
 		flags);
 }