Comment 2 for bug 1208606

StacktraceTop:
 g_type_check_instance_is_a (type_instance=type_instance@entry=0x7fb6640026e0, iface_type=iface_type@entry=80) at /build/buildd/glib2.0-2.37.3/./gobject/gtype.c:3973
 g_object_ref (_object=0x7fb6640026e0) at /build/buildd/glib2.0-2.37.3/./gobject/gobject.c:3054
 closure_invoke_notifiers (notify_type=2, closure=0x7fb66c00f120) at /build/buildd/glib2.0-2.37.3/./gobject/gclosure.c:276
 g_closure_invoke (closure=0x7fb66c00f120, return_value=0x0, n_param_values=2, param_values=0x7fb672d69190, invocation_hint=0x7fb672d69130) at /build/buildd/glib2.0-2.37.3/./gobject/gclosure.c:776
 signal_emit_unlocked_R (node=node@entry=0xdc3a90, detail=detail@entry=629, instance=instance@entry=0x7fb66c003eb0, emission_return=emission_return@entry=0x0, instance_and_params=instance_and_params@entry=0x7fb672d69190) at /build/buildd/glib2.0-2.37.3/./gobject/gsignal.c:3582