[combo-box] Add API to re-enable focusing the selected item

[web-padawan]

Describe your motivation

In #6055, we removed logic responsible for scrolling the selected item into the viewport and marking it as focused.

While this improves UX with dataProvider, it also makes UX worse when using items in the web component.

Describe the solution you'd like

Consider adding a new boolean property e.g. focusSelectedItem that would enable the old logic (false by default).

[MrLightWood]

Any update on adding this feature? I wanted to update to version 24 from 23, but can't do it due to scrolling into the view feature being removed. It is very crucial to me.

[TatuLund]

There is an API, but it is private

https://gist.github.com/TatuLund/c01ffca58869754ea6b419b8c2cbc03b