#imagePreView '(self componentAt:#imagePreView) subViews' throws exception, because 'subViews' is an empty array at closing the image editor fixed to return nil if subViews isEmptyOrNil

LIBRARY         libtool2
DESCRIPTION     'Smalltalk/X Programmer Tool Classes 2'
CODE            PRELOAD MOVEABLE DISCARDABLE
SEGMENTS
    INITCODE    PRELOAD DISCARDABLE
EXPORTS
    __libtool2_Init     @1