Use an ES6 class in ListView docs

Reviewed By: mkonicek

Differential Revision:
D3723141
Ninja: docs only

fbshipit-source-id: e1030f85b524777d2efbedb3cf78c218c34bad88

Libraries/CustomComponents/ListView/ListView.js

@@ -65,21 +65,24 @@ var DEFAULT_SCROLL_CALLBACK_THROTTLE = 50;
  * Minimal example:
  *
  * ```
- * getInitialState: function() {
- *   var ds = new ListView.DataSource({rowHasChanged: (r1, r2) => r1 !== r2});
- *   return {
+ * class MyComponent extends Component {
+ *   constructor() {
+ *     super();
+ *     const ds = new ListView.DataSource({rowHasChanged: (r1, r2) => r1 !== r2});
+ *     this.state = {
  *       dataSource: ds.cloneWithRows(['row 1', 'row 2']),
  *     };
- * },
+ *   }
  *
- * render: function() {
+ *   render() {
  *     return (
  *       <ListView
  *         dataSource={this.state.dataSource}
  *         renderRow={(rowData) => <Text>{rowData}</Text>}
  *       />
  *     );
- * },
+ *   }
+ * }
  * ```
  *
  * ListView also supports more advanced features, including sections with sticky