##### 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
- List of fields which are not needed to collect.
    - "Supports elements: C(db_size). Unsupported elements will be ignored"
    type: list
    elements: str
    version_added: '2.10'
notes:
- Calculating the size of a database might be slow, depending on the number and size of tables in it.
  To avoid this, use I(exclude_fields=db_size).
seealso:
- module: mysql_variables
- module: mysql_db
- module: mysql_user
- module: mysql_replication
author:
- Andrew Klychkov (@Andersson007)
extends_documentation_fragment: mysql
'''
EXAMPLES = r'''
# Display info from mysql-hosts group (using creds from ~/.my.cnf to connect):
# ansible mysql-hosts -m mysql_info
# Display only databases and users info:
# ansible mysql-hosts -m mysql_info -a 'filter=databases,users'
# Display only slave status:
# ansible standby -m mysql_info -a 'filter=slave_status'
# Display all info from databases group except settings:
# ansible databases -m mysql_info -a 'filter=!settings'
- name: Collect all possible information using passwordless root access
  mysql_info:
    login_user: root
- name: Get MySQL version with non-default credentials