code: function getParentRole(elm) {
          var role, parent = elm || focusedElement;
  
          while ((parent = parent.parentNode)) {
            if ((role = getRole(parent))) {
              return role;
            }
          }
        }
docs: Returns the wai role of the parent element of the currently
  focused element or specified element.
  
  @private
  @param {Element} elm Optional element to get parent role from.
  @return {String} Role of the first parent that has a role.