##### SUMMARY

`mysql_info` module doesn't show empty DBs. It uses following query in the code:

```
MariaDB [(none)]> SELECT table_schema AS 'name', SUM(data_length + index_length) AS "size" FROM information_schema.TABLES GROUP BY table_schema;
+--------------------+-----------+
| name               | size      |
+--------------------+-----------+
| d106953_tm         | 470728704 |
| information_schema |    212992 |
| mysql              |   6038300 |
| performance_schema |         0 |
+--------------------+-----------+
4 rows in set (0,005 sec)
```
But `show databases` show something else;
```
MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| d106953_tm         |
| information_schema |
| innodb             |
| mysql              |
| performance_schema |
| testovic           |
| tm_web             |
| ttttt              |
+--------------------+
8 rows in set (0,001 sec)
```

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
`mysql_info` modules

##### ANSIBLE VERSION
```
ansible 2.9.1
  config file = /home/jiri/.ansible.cfg
  configured module search path = ['/home/jiri/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /home/jiri/stow/ansible/venv/lib/python3.6/site-packages/ansible
  executable location = /home/jiri/stow/ansible/venv/bin/ansible
  python version = 3.6.9 (default, Nov  7 2019, 10:44:02) [GCC 8.3.0]

```

##### OS / ENVIRONMENT
Amazon Linux 2
rh-mariadb103-3.3-5.el7.x86_64

##### STEPS TO REPRODUCE

* create empty via eg. via `mysql_db module`
* query via `mysql_info` what databases where found

##### EXPECTED RESULTS
should list even empty DBs

##### ACTUAL RESULTS

it seems only populated DBs are listed
'metadata_version': '1.1',
    'status': ['preview'],
    'supported_by': 'community'
}
DOCUMENTATION = r'''
---
module: mysql_info
short_description: Gather information about MySQL servers
description:
- Gathers information about MySQL servers.
version_added: '2.9'
options:
  filter:
    description:
    - Limit the collected information by comma separated string or YAML list.
    - Allowable values are C(version), C(databases), C(settings), C(global_status),
      C(users), C(engines), C(master_status), C(slave_status), C(slave_hosts).
    - By default, collects all subsets.
    - You can use '!' before value (for example, C(!settings)) to exclude it from the information.
    - If you pass including and excluding values to the filter, for example, I(filter=!settings,version),
      the excluding values, C(!settings) in this case, will be ignored.
    type: list
    elements: str
  login_db:
    description:
    - Database name to connect to.
    - It makes sense if I(login_user) is allowed to connect to a specific database only.
    type: str
  exclude_fields:
    description: