Fixed the hideable scrollbar appearing behind the items in Chrome & Safari
Fixed the hideable scrollbar appearing behind the items in Chrome & Safari

In Chrome and Safari the hideable scrollbar appeared behind the items.

These changes fixed the issue for Safari 9+ and Chrome. Unfortunately,
applying the same approach for Safari 8 hides the scrollbar completely.
Therefore this fix was targeted for Safari 9 and above. The rendering
in Safari 8 remains incorrent.

vaadin/vaadin-combo-box,vaadin/vaadin-combo-box