Given a .gaSegmentFilter object, or an object that can be coerced to a
.gaSegmentFilter object, set the negation and/or scope
of that .gaSegmentFilter object as per the non-missing arguments.
setSegmentFilterScopeNegation(object, negation, scope)a .gaSegmentFilter object, or an object that can be
coerced to a .gaSegmentFilter object.
optional boolean value of TRUE or FALSE.
optional either "sessions" or "users".
a .gaSegmentFilter object.