EDataBookFactory: Work around a GDBus name watching bug.
EDataBookFactory: Work around a GDBus name watching bug.

Calling g_bus_unwatch_name() from a GBusNameVanished callback will
corrupt the function arguments.  Work around this GDBus bug [1] by
unwatching the bus name last in the callback.

[1] https://bugzilla.gnome.org/706088

Distrotech/evolution-data-server,tintou/evolution-data-server,matzipan/evolution-data-server,matzipan/evolution-data-server,tintou/evolution-data-server,Distrotech/evolution-data-server,tintou/evolution-data-server,Distrotech/evolution-data-server,matzipan/evolution-data-server,Distrotech/evolution-data-server,Distrotech/evolution-data-server,matzipan/evolution-data-server,tintou/evolution-data-server,matzipan/evolution-data-server