Undocumented breaking API change - LayoutGroup.SetChildAlongAxis

There has been a breaking change in the `UnityEngine.UI.LayoutGroup` base class.

In 2018.3 this method had the signature:

protected void SetChildAlongAxis(RectTransform rect, int axis, float pos, float size);

In 2019.1b3 this method has two overloads with these signatures:

protected void SetChildAlongAxis(RectTransform rect, int axis, float scaleFactor, float pos);

protected void SetChildAlongAxis(RectTransform rect, int axis, float scaleFactor, float pos, float size);

All existing uses of this method in 3rd party code have been broken by the introduction of the new "scaleFactor" parameter in the middle of the parameter list. Ideally the new parameter would be placed at the end of the parameter list and default to a value that maintains the existing behaviour of this method.

I couldn't see any mention of this change in the release notes for 2019.1