TracAdmin does not display a restricted list of possible Component owners

[Ryan J Ollos]

The get_user_list​ method of the ComponentAdminPanel class executes a query to retrieve the list of possible users that will be suggested as Component owners when tab-completing the command: SELECT DISTINCT username FROM permission. When [ticket] restrict_owner is True, the list of possible owners for a Component is determined from the known users that have TICKET_MODIFY permission​.

For an environment in which only user1 and user2 have a valid authenticated session but I've assigned permissions to several other users, I see:

> component add component4 
anonymous      group2         user2          user4          
authenticated  user1          user3          user5