Selectable list focus handling

[jurokapsiar]

Feature Request

Selectable list has a specific focus handling:

• The list itself needs to have tabindex=0 by default
• When the list is focused, its tabindex needs to be changed to -1, the tabindex of the currently navigable item needs to be set to 0. Consequently, that item needs to be focused.
• When the list and listitems loose focus, tabindex of the items should be set to -1 and tabindex of the list should be set to 0.

MVP

See listbox examples in http://a11y-guidelines.orange.com/web_EN/exemples.html