* gdk/win32/*.c: Add last argument to g_type_register_static()
calls.
* gdk/win32/gdkwindow-win32.c: Silence gcc -Wall.
* gdk/win32/gdkevents-win32.c: Handle MSH_MOUSEWHEEL messages
generated by older wheel mouse drivers. Get the correct y
coordinate from WM_MOUSEWHEEL messages.