Metaplugin can not be used with router service-type plugin

[Itsuro Oda]

When the metaplugin is selected as the core plugin and a router service-type plugin is specified at the same time (see below), quantum-server crashes with the following error.

--- neutron.conf ---
service_plugins = neutron.services.l3_router.l3_router_plugin.L3RouterPlugin
core_plugin = neutron.plugins.metaplugin.meta_neutron_plugin.MetaPluginV2
---

--- error log ---
2013-12-19 16:07:21.282 TRACE neutron File "/opt/stack/neutron/neutron/manager.py", line 176, in _load_service_plugins
2013-12-19 16:07:21.282 TRACE neutron plugin_inst.get_plugin_type())
2013-12-19 16:07:21.282 TRACE neutron ValueError: (u'Multiple plugins for service %s were configured', 'L3_ROUTER_NAT')
---

Core plugins are going to not support the router extension. The metaplugin should be able to be used with a router service-type plugin.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/65034

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/65034
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=c04785e0ced18ebab6bada1d3961c1394c541a69
Submitter: Jenkins
Branch: master

commit c04785e0ced18ebab6bada1d3961c1394c541a69
Author: Itsuro Oda <email address hidden>
Date: Mon Jan 6 15:03:14 2014 +0900

    Make metaplugin be used with a router service plugin

    "l3_plugin_list" configuration parameter of the metaplugin is permitted
    blank now.
    If "l3_plugin_list" is blank, router extension and extensions which extend
    the router extension don't be included in "supported-extension-aliases" of
    the metaplugin.
    This makes the metaplugin be able to be used with a router service plugin.
    Note that if "l3_plugin_list" is not blank, a router service plugin must
    not be specified, otherwise the error of the bug report still occurs.

    This patch removes some router extension related meaningless codes also.
    (e.g. external-net extension belongs to L2 functionality and be handled
     by core plugins properly.)

    Closes-bug: 1266347
    DocImpact

    Change-Id: I0454bc0a4bd7eda5dad18b0538fb7baebe0b9f91