Moved ScrollWindowEx implementation to the graphics driver.

diff --git a/include/user.h b/include/user.h
index 494f7f3..6837989 100644
--- a/include/user.h
+++ b/include/user.h
@@ -75,6 +75,7 @@
     BOOL   (*pDestroyWindow)(HWND);
     BOOL   (*pGetDC)(HWND,HDC,HRGN,DWORD);
     BOOL   (*pEnableWindow)(HWND,BOOL);
+    INT    (*pScrollWindowEx)(HWND,INT,INT,const RECT*,const RECT*,HRGN,LPRECT,UINT);
     void   (*pSetFocus)(HWND);
     HWND   (*pSetParent)(HWND,HWND);
     BOOL   (*pSetWindowPos)(WINDOWPOS *);