XmlListModel.reload appends rather than reloads

In 4.6.0 XmlListModel.reload did the right thing - it cleared down the model and reloaded it.

In 4.7 TP it looks like reload() is not clearing the existing data which results in a duplicate set every time its called.

I have attached an example which reproduces the problem. Clicking on the red rectangle should reload the model but instead it appends duplicates.