[Ohrrpgce] SVN: teeemcee/10281 Fix PageUp going off the top of MenuDef menus (and crashing)

[subversion at HamsterRepublic.com]

teeemcee
2018-03-31 06:40:34 -0700 (Sat, 31 Mar 2018)
238
Fix PageUp going off the top of MenuDef menus (and crashing)

Strangely, this only happened when the mouse was off the window; no idea why.

(I just introduced this bug in r10261.)

Split correct_menu_state_top out from correct_menu_state
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U   wip/menus.bas
U   wip/menus.bi