third attempt to fix 64-bit Lion hidden-window problem

After all the previous attempts, the problem seems almost trivial:
although Apple documents `NSAnyEventMask' as the constant #xFFFFFFFF,
it's actually NSUIntegerMax (and the difference matters in 64-bit
mode).

Merge to 5.2.

original commit: dc912ee6def7a6e8b4edc13c230b367761c5c722

collects/mred/private/wx/cocoa/const.rkt

@@ -16,8 +16,6 @@
 (define NSRoundedBezelStyle 1)
 (define NSRegularSquareBezelStyle 2)
 
-(define NSAnyEventMask #xffffffff)
-
 (define NSLeftMouseDown 1)
 (define NSLeftMouseUp 2)
 (define NSRightMouseDown 3)

collects/mred/private/wx/cocoa/queue.rkt

@@ -312,6 +312,8 @@
                                (custodian-shutdown-all c)))))))
       (set! was-menu-bar #f)))
 
+(define NSAnyEventMask (sub1 (arithmetic-shift 1 (* 8 (ctype-sizeof _NSUInteger)))))
+
 ;; Call this function only in atomic mode:
 (define (check-one-event wait? dequeue?)
   (pre-event-sync wait?)