function getGoodAdds(complexArray, adds) {
        // remove any that are already added here
        return adds.filter(function (a) {
            return a.parent !== complexArray.parent;
        });
    }
An {{#crossLink "Event"}}{{/crossLink}} that fires whenever the contents of this array changed.  This event
    is fired any time a new entity is attached or added to the EntityManager and happens to belong to this collection.
    Adds that occur as a result of query or import operations are batched so that all of the adds or removes to any individual
    collections are collected into a single notification event for each relation array.
    @example
        // assume order is an order entity attached to an EntityManager.
        orders.arrayChanged.subscribe(
            function (arrayChangedArgs) {
                var addedEntities = arrayChangedArgs.added;
                var removedEntities = arrayChanged.removed;
            });
    @event arrayChanged 
    @param added {Array of Entity} An array of all of the entities added to this collection.
    @param removed {Array of Entity} An array of all of the removed from this collection.
    @readOnly