function Mark$1(params) {
    Transform.call(this, null, params);
  }
Bind scenegraph items to a scenegraph mark instance.
@constructor
@param {object} params - The parameters for this operator.
@param {object} params.markdef - The mark definition for creating the mark.
  This is an object of legal scenegraph mark properties which *must* include
  the 'marktype' property.