Krzysztof Kotlarek 38c3a44bf9
FIX: return empty array when no parent for range ()
If parent element for range does not exists, range calculator should
return empty array. In that case duration calculations will stop because
of:

```
if (_rangeElements(element).length === 2) {
  opts.duration = _calculateDuration(element);
}
```
2021-09-20 16:03:02 +10:00
..