code: function(ids) {
              this.remove(_.difference(this.trackedIds, ids));
              parentInstance.registerIds(ids, ownerKey);
              this.trackedIds = ids;
            }
docs: Pass a list of ids to begin tracking. This will reset any previous list of ids being tracked.
  Overrides the Id registration system to route via the parent collection
  @method requesterMixin.trackIds
  @param ids The list of ids that this collection wants to track