Moved all Win16 definitions out of the standard Windows headers.

diff --git a/controls/listbox.c b/controls/listbox.c
index 4358c79..5ebd498 100644
--- a/controls/listbox.c
+++ b/controls/listbox.c
@@ -2830,7 +2830,7 @@
     case WM_DRAGMOVE:
 	if( !descr->lphc )
         {
-            LPDRAGINFO dragInfo = (LPDRAGINFO)PTR_SEG_TO_LIN( (SEGPTR)lParam );
+            LPDRAGINFO16 dragInfo = (LPDRAGINFO16)PTR_SEG_TO_LIN( (SEGPTR)lParam );
             dragInfo->l = LISTBOX_GetItemFromPoint( wnd, descr, dragInfo->pt.x,
                                                 dragInfo->pt.y );
             return SendMessageA( descr->owner, msg, wParam, lParam );
diff --git a/controls/menu.c b/controls/menu.c
index c536043..f154e3d 100644
--- a/controls/menu.c
+++ b/controls/menu.c
@@ -2205,7 +2205,7 @@
  *
  * Walks menu chain trying to find a menu pt maps to.
  */
-static HMENU MENU_PtMenu( HMENU hMenu, POINT16 pt )
+static HMENU MENU_PtMenu( HMENU hMenu, POINT pt )
 {
    POPUPMENU *menu = MENU_GetMenu( hMenu );
    register UINT ht = menu->FocusedItem;
@@ -2749,9 +2749,7 @@
 	if ((msg.message >= WM_MOUSEFIRST) && (msg.message <= WM_MOUSELAST))
 	{
 	    /* Find a menu for this mouse event */
-            POINT16 pt16;
-            CONV_POINT32TO16( &msg.pt, &pt16 );
-	    hmenu = MENU_PtMenu( mt.hTopMenu, pt16 );
+	    hmenu = MENU_PtMenu( mt.hTopMenu, msg.pt );
 
 	    switch(msg.message)
 	    {
diff --git a/controls/scroll.c b/controls/scroll.c
index e59ff52..e1f9740 100644
--- a/controls/scroll.c
+++ b/controls/scroll.c
@@ -1136,7 +1136,8 @@
     case WM_SYSTIMER:
         {
             POINT pt;
-            CONV_POINT16TO32( (POINT16 *)&lParam, &pt );
+            pt.x = SLOWORD(lParam);
+            pt.y = SHIWORD(lParam);
             SCROLL_HandleScrollEvent( hwnd, SB_CTL, message, pt );
         }
         break;