nova flavor-delete fails with InstanceTypeNotFoundByName API error

Problem Description:

When attempting "nova flavor-delete" sometimes an API error occurs, where it seems that the ID passed as a nova CLI argument is mapped to the wrong flavor name, resulting in a "could not be found" 404 error, even though the selected ID is present in the "nova flavor-list" output:

```
[root@heatlt heat]# nova flavor-list
+----+------------+-----------+------+-----------+------+-------+-------------+
| ID | Name | Memory_MB | Disk | Ephemeral | Swap | VCPUs | RXTX_Factor |
+----+------------+-----------+------+-----------+------+-------+-------------+
| 1 | t1.micro | 256 | 0 | 10 | | 1 | 1.0 |
| 8 | m2.2xlarge | 2048 | 0 | 10 | | 2 | 1.0 |
| 9 | m2.4xlarge | 2048 | 0 | 10 | | 2 | 1.0 |
+----+------------+-----------+------+-----------+------+-------+-------------+

[root@heatlt heat]# nova --debug flavor-delete 1
connect: (127.0.0.1, 5000)
send: 'POST /v2.0/tokens HTTP/1.1\r\nHost: 127.0.0.1:5000\r\nContent-Length: 106\r\ncontent-type: application/json\r\naccept-encoding: gzip, deflate\r\naccept: application/json\r\nuser-agent: python-novaclient\r\n\r\n{"auth": {"tenantName": "admin", "passwordCredentials": {"username": "admin", "password": "verybadpass"}}}'
reply: 'HTTP/1.1 200 OK\r\n'
header: Content-Type: application/json
header: Vary: X-Auth-Token
header: Date: Mon, 10 Sep 2012 14:15:08 GMT
header: Transfer-Encoding: chunked
connect: (localhost, 8774)
send: u'DELETE /v1.1/fd7795f68eab47d0906d305e470ab155/flavors/1 HTTP/1.1\r\nHost: localhost:8774\r\nx-auth-project-id: admin\r\nx-auth-token: 1f98c1b6366146ea8a8b70ba1a4cfd31\r\naccept-encoding: gzip, deflate\r\naccept: application/json\r\nuser-agent: python-novaclient\r\n\r\n'
reply: 'HTTP/1.1 404 Not Found\r\n'
header: Content-Length: 78
header: Content-Type: application/json; charset=UTF-8
header: X-Compute-Request-Id: req-ece516fa-cebd-491b-ac66-c24f75bc63c5
header: Date: Mon, 10 Sep 2012 14:15:09 GMT
DEBUG (shell:416) The resource could not be found. (HTTP 404)
Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/novaclient/shell.py", line 413, in main
    OpenStackComputeShell().main(sys.argv[1:])
  File "/usr/lib/python2.7/site-packages/novaclient/shell.py", line 364, in main
    args.func(self.cs, args)
  File "/usr/lib/python2.7/site-packages/novaclient/v1_1/shell.py", line 311, in do_flavor_delete
    cs.flavors.delete(args.id)
  File "/usr/lib/python2.7/site-packages/novaclient/v1_1/flavors.py", line 59, in delete
    self._delete("/flavors/%s" % base.getid(flavor))
  File "/usr/lib/python2.7/site-packages/novaclient/base.py", line 166, in _delete
    resp, body = self.api.client.delete(url)
  File "/usr/lib/python2.7/site-packages/novaclient/client.py", line 145, in delete
    return self._cs_request(url, 'DELETE', **kwargs)
  File "/usr/lib/python2.7/site-packages/novaclient/client.py", line 124, in _cs_request
    **kwargs)
  File "/usr/lib/python2.7/site-packages/novaclient/client.py", line 107, in request
    raise exceptions.from_response(resp, body)
NotFound: The resource could not be found. (HTTP 404)
ERROR: The resource could not be found. (HTTP 404)
```

There is a backtrace in the nova API log, which seems to suggest the ID (t1.micro) is being mapped to the wrong name ( m1.tiny), full backtrace attached.

```
2012-09-10 15:15:09 TRACE nova.api.openstack File "/usr/lib/python2.7/site-packages/nova/api/openstack/compute/contrib/flavormanage.py", line 49, in _delete
2012-09-10 15:15:09 TRACE nova.api.openstack instance_types.destroy(flavor['name'])
2012-09-10 15:15:09 TRACE nova.api.openstack File "/usr/lib/python2.7/site-packages/nova/compute/instance_types.py", line 87, in destroy
2012-09-10 15:15:09 TRACE nova.api.openstack raise exception.InstanceTypeNotFoundByName(instance_type_name=name)
2012-09-10 15:15:09 TRACE nova.api.openstack InstanceTypeNotFoundByName: Instance type with name m1.tiny could not be found.
2012-09-10 15:15:09 TRACE nova.api.openstack
2012-09-10 15:15:09 INFO nova.api.openstack [req-ece516fa-cebd-491b-ac66-c24f75bc63c5 0c8a0190783648159f3e4b4fd2aaca03 fd7795f68eab47d0906d305e470ab155] http://localhost:8774/v1.1/fd7795f68eab47d0906d305e470ab155/flavors/1 returned with HTTP 404
```

Test environment : Fedora 17, package versions as follows:

$ rpm -qa | grep nova
openstack-nova-volume-2012.1.1-15.fc17.noarch
python-nova-2012.1.1-15.fc17.noarch
openstack-nova-cert-2012.1.1-15.fc17.noarch
openstack-nova-scheduler-2012.1.1-15.fc17.noarch
python-novaclient-2012.1-2.fc17.noarch
openstack-nova-compute-2012.1.1-15.fc17.noarch
openstack-nova-api-2012.1.1-15.fc17.noarch
openstack-nova-2012.1.1-15.fc17.noarch
openstack-nova-objectstore-2012.1.1-15.fc17.noarch
openstack-nova-console-2012.1.1-15.fc17.noarch
openstack-nova-common-2012.1.1-15.fc17.noarch
openstack-nova-network-2012.1.1-15.fc17.noarch

Reproducer:

Running the heat-api "tools/nova_create_flavors.sh" script multiple times will reliably trigger this bug.

This script deletes all current flavors, and creates a predefined set of flavors. It will work once, then on the second run it nearly always errors on one flavor-delete. Copy of this script is attached below.