function makeInner() {
  var key = '__ec_inner_' + innerUniqueIndex++;
  return function (hostObj) {
    return hostObj[key] || (hostObj[key] = {});
  };
}
Enable property storage to any host object.
Notice: Serialization is not supported.

For example:
let inner = zrUitl.makeInner();

function some1(hostObj) {
     inner(hostObj).someProperty = 1212;
     ...
}
function some2() {
     let fields = inner(this);
     fields.someProperty1 = 1212;
     fields.someProperty2 = 'xx';
     ...
}

@return {Function}