VLCKit: fix a deadlock case in VLCEventManager
VLCKit: fix a deadlock case in VLCEventManager

There is a case of recursion over mutexed code when cancelling calls for an object that may itself dealloc other objects with pending events (this has been witnessed)

Signed-off-by: Felix Paul Kühne <af44a38b4065def9b90f0b66e4658837dd45b77d@videolan.org>

kamcord/VLCKit,waterskier2007/VLCKit,hpsoar/VLCKit,simon1984/test,programming086/VLCKit,simon1984/test,kamcord/VLCKit,siuying/VLCKit,hpsoar/VLCKit,larrytin/VLCKit,siuying/VLCKit,simon1984/test,waterskier2007/VLCKit,programming086/VLCKit,CollabraMusic/VLCKit,waterskier2007/VLCKit,larrytin/VLCKit,siuying/VLCKit,CollabraMusic/VLCKit,strukturag/VLCKit,strukturag/VLCKit,kamcord/VLCKit,CollabraMusic/VLCKit