Export data module: a chart without a title throws error when trying to export data

[KacperMadej]

Behaviour

It's caused by title not having textStr at

highcharts/js/modules/export-data.src.js

Line 445 in d7394ee

name = this.title.textStr.replace(/ /g, '-').toLowerCase();

Live demo with steps to reproduce

http://jsfiddle.net/BlackLabel/0jtoo0th/4/
Export through menu to CSV or XML gives error in console and file is not downloaded.

Workaround

Set filename: http://jsfiddle.net/BlackLabel/0jtoo0th/3/