Hyper-V agent cannot disconnect orphaned switch ports

[Claudiu Belu]

On Windows / Hyper-V Server 2008 R2, when a switch port have to be disconnected because the VM using it was removed,
DisconnectSwitchPort will fail, returning an error code and a HyperVException is raised. If the exception is raised, the switch port is not removed and will make the WMI operations more expensive.

If the VM's VNIC has been removed, disconnecting the switch port is no longer necessary and it should be removed.

Trace:
http://paste.openstack.org/show/115297/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/124151

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/juno
Review: https://review.openstack.org/161273

[OpenStack Infra (hudson-openstack)]

Change abandoned by Claudiu Belu (<email address hidden>) on branch: master
Review: https://review.openstack.org/124151
Reason: This bug no longer affects master, since the Hyper-V Neutron Agent will be decomposed from master. But this bug still affects the stable branches. Cherry-picked to Juno: https://review.openstack.org/#/c/161273/

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/161273
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=1dcb072bebd31094623555a4f387bafc9712820e
Submitter: Jenkins
Branch: stable/juno

commit 1dcb072bebd31094623555a4f387bafc9712820e
Author: Claudiu Belu <email address hidden>
Date: Thu Sep 25 19:03:45 2014 +0300

    Fixes Hyper-V agent port disconnect issue

    On Windows / Hyper-V Server 2008 R2, when a switch port
    have to be disconnected because the VM using it was
    removed, DisconnectSwitchPort will fail, returning an
    error code and a HyperVException is raised.

    If the VM's VNIC has been removed, disconnecting the
    switch port is no longer necessary and the it will
    proceed to remove the switch port.

    This issue is not present in Windows / Hyper-V Server 2012,
    as the switch ports are cleaned automatically.

    Note: This commit is not a classic backport, as this commit is not
    merged in master, since the Hyper-V Neutron Agent was decomposed
    from the master branch. This commit is already included in the
    networking_hyperv project:
    https://github.com/stackforge/networking-hyperv/commit/f5956a34d09d6468a0645c541cba1a92b9938fc1

    (cherry picked from commit 2e8fe958eb68e04b5b608d2d4dd53973193a931f)

    Conflicts:
     neutron/plugins/hyperv/agent/hyperv_neutron_agent.py

    Closes-Bug: #1374108

    Change-Id: I729753c15c51c86655651b132fcf8eab78884eb5