bfb0bc7a29
Set the accessible states of the switcherList items by calling a function instead of manipulating class-internal variables from outside the class, which is considered bad practice. The check whether the item at `_selectedIndex` exists can also be removed since we always select a new index after an item was removed (i.e. an app was closed) and destroy the alt-tab switcher right away if no more items exist (see `SwitcherPopup._itemRemovedHandler`). https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/167