DOMException when tasks array is empty

> Uncaught DOMException: Failed to execute 'removeChild' on 'Node': The node to be removed is not a child of this node.

This happens when tasks goes empty ([], length 0, you get the point).

This renders the whole thing useless.

```
{
this.state.tasks.length
?

:

{this.props.t('info.emptyProjectProgress')}

}
```

As soon as state.tasks.length goes to 0, everything goes bust.