Description of problem:
Creating a HTTPS pool with assignment to HTTP listener ends up with the pool in error state and the following error octavia worker log: 
http://paste.openstack.org/show/771268/

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1. Create LB , Create HTTP listener
2. Create HTTPS pool. See pool status and worker log. 
3.

Actual results:
(tester) [stack@undercloud-0 ~]$  openstack loadbalancer pool list 
+--------------------------------------+------+----------------------------------+---------------------+----------+--------------+----------------+
| id                                   | name | project_id                       | provisioning_status | protocol | lb_algorithm | admin_state_up |
+--------------------------------------+------+----------------------------------+---------------------+----------+--------------+----------------+
| 17d7f394-01e8-48cb-ac90-ea2217cad544 |      | 85cdc4a3fc924852aa7c3d69efdb4ebb | ERROR               | HTTPS    | ROUND_ROBIN  | True           |
+--------------------------------------+------+----------------------------------+---------------------+----------+--------------+----------------+
(tester) [stack@undercloud-0 ~]$  openstack loadbalancer pool show 17d7f394-01e8-48cb-ac90-ea2217cad544
+----------------------+--------------------------------------+
| Field                | Value                                |
+----------------------+--------------------------------------+
| admin_state_up       | True                                 |
| created_at           | 2019-09-05T09:42:09                  |
| description          |                                      |
| healthmonitor_id     |                                      |
| id                   | 17d7f394-01e8-48cb-ac90-ea2217cad544 |
| lb_algorithm         | ROUND_ROBIN                          |
| listeners            | ceecab22-1966-4c15-828c-09d8d6eced39 |
| loadbalancers        | 3a3a3df8-79da-45fe-8701-76ab0d03170c |
| members              |                                      |
| name                 |                                      |
| operating_status     | OFFLINE                              |
| project_id           | 85cdc4a3fc924852aa7c3d69efdb4ebb     |
| protocol             | HTTPS                                |
| provisioning_status  | ERROR                                |
| session_persistence  | None                                 |
| updated_at           | 2019-09-05T09:42:09                  |
| tls_container_ref    | None                                 |
| ca_tls_container_ref | None                                 |
| crl_container_ref    | None                                 |
| tls_enabled          | False                                |
+----------------------+--------------------------------------+
(tester) [stack@undercloud-0 ~]$ 


Expected results:
The pool should be created ok and traffic from pool to members should be https. 

Additional info: