Add screen reader support to dropbutton, prevent from closing on focusout.
- Add aria-expanded attribute to toggle button
- Add unique ids to secondary actions
- Add aria-controls attribute to toggle button, with list of secondary action ids
- Change toggle button's screenreader text from "List additional actions" to "Additional actions"
- Stop dropbutton menu from closing automatically on focusout
- Add Nightwatch test
Edited by Camille Davis