Comment 2 for bug 834348

StacktraceTop:
 g_type_check_instance_cast (type_instance=0x86024a0, iface_type=141933256) at /build/buildd/glib2.0-2.29.16/./gobject/gtype.c:3985
 adapter_changed (adapter=0x860f010, property=0x866d9d0 "Discovering", value=0x87290e8, user_data=0x86024a0) at bluetooth-client.c:616
 marshal_VOID__STRING_BOXED (closure=0x867cc78, return_value=0x0, n_param_values=3, param_values=0x879bfb0, invocation_hint=0xbff3d970, marshal_data=0x0) at marshal.c:93
 marshal_dbus_message_to_g_marshaller (closure=0x867cc78, return_value=0x0, n_param_values=3, param_values=0x86f8908, invocation_hint=0xbff3d970, marshal_data=0x0) at dbus-gproxy.c:1733
 g_closure_invoke (closure=0x867cc78, return_value=0x0, n_param_values=3, param_values=0x86f8908, invocation_hint=0xbff3d970) at /build/buildd/glib2.0-2.29.16/./gobject/gclosure.c:773