we always invoke the destroy notifiers for user_data and source_data
after execution of dispatch(). thus, g_source_destroy_func() will always
be called within the main_loop lock (this wasn't really assured
before), and can release and reaquire the look around destroy notifier
we always invoke the destroy notifiers for user_data and source_data
after execution of dispatch(). thus, g_source_destroy_func() will always
be called within the main_loop lock (this wasn't really assured
before), and can release and reaquire the look around destroy notifier