faild to list network due to the provider:vlan_id

[yong sheng gong]

to reproduce:
quantum net-create myname
quantum port-create <netid>
quantum net-delete <netid>

quantum net-list
ERROR: cliff.app NetworkVlanBinding for network 01e4c6f0-f831-4ec6-a7b8-754d4a08b765 does not exist

sample execution seq after: https://review.openstack.org/#/c/10452
[root@robinlinux ~]# quantum net-create myname
Created a new network:
+------------------+--------------------------------------+
| Field | Value |
+------------------+--------------------------------------+
| admin_state_up | True |
| id | 01e4c6f0-f831-4ec6-a7b8-754d4a08b765 |
| name | myname |
| provider:vlan_id | 1000 |
| status | ACTIVE |
| subnets | |
| tenant_id | 9d049e4b60b64716978ab415e6fbd5c0 |
+------------------+--------------------------------------+
[root@robinlinux ~]# quantum net-list
+----------------+--------------------------------------+--------+------------------+--------+---------+----------------------------------+
| admin_state_up | id | name | provider:vlan_id | status | subnets | tenant_id |
+----------------+--------------------------------------+--------+------------------+--------+---------+----------------------------------+
| True | 01e4c6f0-f831-4ec6-a7b8-754d4a08b765 | myname | 1000 | ACTIVE | | 9d049e4b60b64716978ab415e6fbd5c0 |
+----------------+--------------------------------------+--------+------------------+--------+---------+----------------------------------+
[root@robinlinux ~]# quantum port-create 01e4c6f0-f831-4ec6-a7b8-754d4a08b765 --name myport
Created a new port:
+----------------+--------------------------------------+
| Field | Value |
+----------------+--------------------------------------+
| admin_state_up | True |
| device_id | |
| fixed_ips | |
| id | 2072a5e1-1d1a-43a5-bcb2-c9b17b99a7a7 |
| mac_address | fa:16:3e:7e:94:de |
| name | myport |
| network_id | 01e4c6f0-f831-4ec6-a7b8-754d4a08b765 |
| status | ACTIVE |
| tenant_id | 9d049e4b60b64716978ab415e6fbd5c0 |
+----------------+--------------------------------------+
[root@robinlinux ~]# quantum net-list
+----------------+--------------------------------------+--------+------------------+--------+---------+----------------------------------+
| admin_state_up | id | name | provider:vlan_id | status | subnets | tenant_id |
+----------------+--------------------------------------+--------+------------------+--------+---------+----------------------------------+
| True | 01e4c6f0-f831-4ec6-a7b8-754d4a08b765 | myname | 1000 | ACTIVE | | 9d049e4b60b64716978ab415e6fbd5c0 |
+----------------+--------------------------------------+--------+------------------+--------+---------+----------------------------------+
[root@robinlinux ~]# quantum net-delete myname
ERROR: cliff.app Unable to complete operation on network 01e4c6f0-f831-4ec6-a7b8-754d4a08b765. There is one or more attachments plugged into its ports.
[root@robinlinux ~]# quantum net-list
ERROR: cliff.app NetworkVlanBinding for network 01e4c6f0-f831-4ec6-a7b8-754d4a08b765 does not exist

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/10466

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/10466
Committed: http://github.com/openstack/quantum/commit/bc3d89c5ab618972641e0afe2f691b6251333374
Submitter: Jenkins
Branch: master

commit bc3d89c5ab618972641e0afe2f691b6251333374
Author: Gary Kotton <email address hidden>
Date: Sat Jul 28 14:08:47 2012 -0400

    Only delete VLAN information after Quantum network is deleted

    Fixes bug 1030271

    In the case where a network is deleted and there is a VLAN tag in a
    separate table then the tag should only be deleted if the network
    is deleted.

    Change-Id: I99130f863928abf30a521e9a2b6d1233a274d9c6