If message is not of type gio.types.DBusMessageType.Error does nothing and returns false.
Otherwise this method encodes the error in message as a #GError using g_dbus_error_set_dbus_error() using the information in the gio.types.DBusMessageHeaderField.ErrorName header field of message as well as the first string item in message's body.
true if error was set, false otherwise.
If message is not of type gio.types.DBusMessageType.Error does nothing and returns false.
Otherwise this method encodes the error in message as a #GError using g_dbus_error_set_dbus_error() using the information in the gio.types.DBusMessageHeaderField.ErrorName header field of message as well as the first string item in message's body.