Comment 2 for bug 758478

StacktraceTop:
 g_type_check_instance_cast (type_instance=0x20a3ef0, iface_type=37110608) at /build/buildd/glib2.0-2.28.5/./gobject/gtype.c:3994
 bamf_factory_view_for_path (factory=0x21e1ec0, path=0x2f7fca0 "/org/ayatana/bamf/application0xeb6f20") at bamf-factory.c:203
 bamf_matcher_on_view_opened (proxy=<value optimized out>, path=0x2f7fca0 "/org/ayatana/bamf/application0xeb6f20", type=<value optimized out>, matcher=0x1f5d940) at bamf-matcher.c:128
 marshal_dbus_message_to_g_marshaller (closure=0x20f8c10, return_value=0x0, n_param_values=<value optimized out>, param_values=<value optimized out>, invocation_hint=0x7fff0a8b4430, marshal_data=0x0) at dbus-gproxy.c:1681
 g_closure_invoke (closure=0x20f8c10, return_value=0x0, n_param_values=3, param_values=0x242d540, invocation_hint=0x7fff0a8b4430) at /build/buildd/glib2.0-2.28.5/./gobject/gclosure.c:767