OF Plugin changes the order of NodeConnector update events.

Due to this issue, VTN Manager system test fails.
https://jenkins.opendaylight.org/integration/job/integration-master-csit-karaf-vtn-only/
https://lists.opendaylight.org/pipermail/integration-dev/2014-September/001687.html

The MD-SAL OF plugin changed the order of NodeConnector update events from OenFlow 1.0 switches.

For example, when I run a controller and a Mininet, and start OpenFlow 1.0 switches on it, a switch sent FEATURES_REPLY message and PORT_STATUS message to the controller.
When the switch sent the FEATURES_REPLY, a port "s1-eth1" was LINK_DOWN, so The FEATURES_REPLY contained information which indicated the status of the port "s1-eth1" is "LINK_DOWN".
After that, the port "s1-eth1" became LINK_UP, and the switch sent the PORT_STATUS message which indicated "s1-eth1" was "LINK_UP".

However, the MD-SAL OF plugin changed the order of these notification.

Therefore, VTN Manager (an application of SAL) received "LINK_UP" notification at first, and received "LINK_DOWN" notification at second for the port.
VTN Manager thought that the status of the port changed from "LINK_UP" to "LINK_DOWN", it stopped to send PACKET_OUT for the port, and stopped to install flow entry which used the port.