gvfschannel: do not call close job if channel is blocked
gvfschannel: do not call close job if channel is blocked

We don't want to call new jobs when backend is force unmounted.

https://bugzilla.gnome.org/show_bug.cgi?id=737842

gicmo/gvfs,gicmo/gvfs,gicmo/gvfs,gicmo/gvfs