old_contents: import Mixin from '@ember/object/mixin';
  
  export default Mixin.create({
  
    _createInternalModel(name, parent, opts={}) {
      opts.database = this;
      return this.get('store')._createInternalModel(name, parent, opts);
    },
  
    _createInternalModels(name, parent, source, opts={}) {
      opts.props = opts.props || {};
      opts.props.database = this;
      return this.get('store')._createInternalModels(name, parent, source, opts);
    },
  
    model(name, opts) {
      return this._createInternalModel(name, null, opts).model(true);
    },
  
    models(name, source, opts) {
      return this._createInternalModels(name, null, source, opts).model(true);
    }
  
  });
  
new_contents: import Mixin from '@ember/object/mixin';
  
  export default Mixin.create({
  
    _createInternalModel(name, parent, opts={}, _ref) {
      opts.database = this;
      return this.get('store')._createInternalModel(name, parent, opts, _ref);
    },
  
    _createInternalModels(name, parent, source, opts={}) {
      opts.props = opts.props || {};
      opts.props.database = this;
      return this.get('store')._createInternalModels(name, parent, source, opts);
    },
  
    model(name, opts) {
      return this._createInternalModel(name, null, opts).model(true);
    },
  
    models(name, source, opts) {
      return this._createInternalModels(name, null, source, opts).model(true);
    }
  
  });
  
subject: add _ref param for internal model