old_contents: import Em from 'ember';
  import { defaultValue } from 'llama-table/computed';
  var computed = Em.computed;
  var alias = computed.alias;
  var reads = computed.reads;
  
  /**
   * Adds some extra properties to row definitions.
   * @module controllers
   * @constructor
   * @class RowController
   * @extends Ember.ObjectProxy
   */
  var RowController = Em.ObjectProxy.extend({
  	content: alias('model'),
  	contentIndex: computed('parentController.@each', function () {
  		var array = this.get('parentController');
  		var content = this;
  		var index = array.indexOf(content);
  		return index;
  	}),
  	isExpanded: false,
  	height: defaultValue('model.height', 30),
  	subcontentHeight: reads('height')
  });
  
  export default RowController;
  
new_contents: import Em from 'ember';
  import { defaultValue } from 'llama-table/computed';
  var makeArray = Em.makeArray;
  var computed = Em.computed;
  var alias = computed.alias;
  var reads = computed.reads;
  
  /**
   * Adds some extra properties to row definitions.
   * @module controllers
   * @constructor
   * @class RowController
   * @extends Ember.ObjectProxy
   */
  var RowController = Em.ObjectProxy.extend({
  	content: alias('model'),
  	contentIndex: computed('parentController.@each', function () {
  		var array = this.get('parentController');
  		var content = this;
  		var index = makeArray(array).indexOf(content);
  		return index;
  	}),
  	isExpanded: false,
  	height: defaultValue('model.height', 30),
  	subcontentHeight: reads('height')
  });
  
  export default RowController;
  
subject: Make sure parent controller is an array