Description of problem:
When saving a change made to Server Roles (enabling or disabling a Server Role), the server name "EVM" disappears.

Before:
[root@host-192-168-100-98 vmdb]# rake evm:status
Checking EVM status...
 Zone    | Server | Status  | ID |
---------+--------+---------+----+
 default | EVM    | started |  1 |

After disabling Automation Engine server role:
[root@host-192-168-100-98 vmdb]# rake evm:status
Checking EVM status...
 Zone    | Server | Status  | ID |
---------+--------+---------+----+
 default |        | started |  1 |

Version-Release number of selected component (if applicable):
5.9.5.1
Occurs also in 5.9.5.0

How reproducible:
Always

Steps to Reproduce:
1. Navigate to Configuration, settings for the current server
2. In Server Control part, enable or disable a Role
3. Save
4a. SSH to appliance and run
    [root@host-192-168-100-98 ~]# vmdb
    [root@host-192-168-100-98 vmdb]# rake evm:status
4b. Or refresh the page and notice there is no "EVM" behind the current user name

Actual results:
EVM server name disappears when making change in Server Roles

Expected results:
EVM server name shouldn't disappear

Additional info:
Not reproducible on 5.10.0.19.