User picker field misbehaves under Test Steps when Global permissions is removed

Description: User picker field misbehaves under Test Steps when Global permissions is removed.

Pre-conditions. NA

How to reproduce

1. Create a user picker custom field under the Test step custom field.
2. Remove Global permission for Browse users and groups.
3. Now search under that user picker field and it does not search.
4. Users are still searchable under normal user picker fields like assignee. 

NOTE: Jira KB states the same: https://confluence.atlassian.com/jirakb/unable-to-browse-for-users-and-groups-120521888.html
Users without this Browse Users Global Permission would still be able to add users to any user picker field by explicitly providing the exact username - or groupname as the case may be, but will not have auto-suggest working for them.

Actual result/Attachments: The user picker does not show any results. 

Expected result: The user picker field should show users when searched. 

Version

• 
  1.1.91-AC