When the window goes away there's no x window to remove properties from and also the
DBus interface for the menu seems to go away before we could unsubscribe
* Send delayed reply when we aren't subscribed yet in GetLayout
* Show keyboard shortcuts (crude)
* Add some icons for known actions (even more crude)
* Support GTK actions stuff, including action enabled/visible/checkable
* Action invocation
This will mediate between applications using GMenu (like LibreOffice) and expose their menus
using our DBusMenu protocol so that no changes on our global menu side is needed.
WIP: So far all it can do is detect windows with GMenus attached to it, register a DBus service
and then announce the corresponding DBusMenu paths.
Kai Uwe Broulik