Comment 4 for bug 1551542

Reviewed: https://review.openstack.org/238745
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=de5bdc9cc2cde9100802d68309fa6dfe3ef31f4d
Submitter: Jenkins
Branch: stable/liberty

commit de5bdc9cc2cde9100802d68309fa6dfe3ef31f4d
Author: Eugene Nikanorov <email address hidden>
Date: Wed Sep 23 14:06:54 2015 +0400

    Consume service plugins queues in RPC workers.

    This patch adds all RPC workers to consumers of service
    plugins queues such as metering and l3-plugin.
    This is important for DVR-enabled deployments with hundreds
    of agents.

    Closes-Bug: #1498844
    (cherry picked from commit 5be613490deebf494f2ecbbcd8cb5dd0d6f5e1b3)

    ===

    Also include the following fix that keeps backwards compatibility with
    plugins that don't implement start_rpc_listeners method:

    Check if plugin supports starting rpc listeners

    When neutron starts an rpc worker, it checks if the plugin has the method
    "start_rpc_listeners". Since most plugins inherit from a base class, and
    that base class implements the start_rpc_listeners method and raises
    NotImplementedError, the rpc worker will attempt to call that method.
    It should just catch the NotImplementedError and continue on.

    Change-Id: Ie1830b6140acffffd0f283a0d8eefa52067f7650
    Closes-Bug: 1551542
    (cherry picked from commit cd7be292a8d1fb4ce913c4e7fbfc55fda033ffbe)

    ===

    Change-Id: I6fea7f409c91b25d2c35b038d6100fdfa85d1905