code: function () {
      var self = this;
      Meteor._noYieldsAllowed(function () {
        _.each(self._documents, function(collectionDocs, collectionName) {
          // Iterate over _.keys instead of the dictionary itself, since we'll be
          // mutating it.
          _.each(_.keys(collectionDocs), function (strId) {
            self.removed(collectionName, self._idFilter.idParse(strId));
          });
        });
      });
    }
docs: Send remove messages for every document.