Fix https://github.com/mate-desktop/caja/issues/1066 "Caja caches folders from usb drives/disk" Nowadays, we rely on G_FILE_MONITOR_EVENT_UNMOUNTED to be emitted when a mount disappears, since we already monitor the directory, in order to switch the view to a different location. Since non-native mounts very likely won't have file monitoring though, we're not going to receive such events in that case, and fail to redirect the view as a consequence. This patch fixes it by listening to the mount-removed signal on GVolumeMonitor when a monitor is requested for a non-native mount, and emulating a file removal in that case. Backport Nautilus commit gitlab.gnome.org/GNOME/nautilus/commit/3891241ba760c59d284b7579dbd340651c8d4d29 note that caja_get_mounted_mount_for_root had to be added, while the equivalent Nautilus function was from a prior commit