a11y: atk_add_key_event_listener listener_id should not return 0 as a valid value
a11y: atk_add_key_event_listener listener_id should not return 0 as a valid value

cally_util_add_key_event_listener first id returned was 0, but as
the documentation says, this is a reserved value for a wrong id

Fixes https://bugzilla.gnome.org/show_bug.cgi?id=675183

Distrotech/clutter,ebassi/clutter,djdeath/clutter-android,Distrotech/clutter,jigpu/clutter,djdeath/clutter,collects/clutter,jigpu/clutter,heysion/clutter-clone,djdeath/clutter,djdeath/clutter,Distrotech/clutter,djdeath/clutter-android,ebassi/clutter,jigpu/clutter,Distrotech/clutter,heysion/clutter-clone,GNOME/clutter,jigpu/clutter,Distrotech/clutter,GNOME/clutter,collects/clutter,ebassi/clutter,heysion/clutter-clone,collects/clutter,heysion/clutter-clone,ebassi/clutter,Distrotech/clutter,djdeath/clutter,jigpu/clutter,djdeath/clutter-android,GNOME/clutter,collects/clutter,jigpu/clutter,djdeath/clutter,djdeath/clutter-android,djdeath/clutter-android,heysion/clutter-clone,djdeath/clutter,collects/clutter,ebassi/clutter,GNOME/clutter,GNOME/clutter