No host in maintenance icon for users with limited access rights

Steps to reproduce:

1. Create 2 hosts and add them to separate host groups.
2. Create a trigger for each of the hosts.
3. Create 2 maintenance periods for both host groups so that one overlaps the other.
4. Create a regular admin user or simple user with RW permissions to one of the host groups.
5. Open Problems widget configuration and select "Show suppressed problems".
6. Trigger problems.
7. Login as regular admin/simple user and navigate to dashboard.

Result:
Host in maintenance (wrench) icons not being displayed.
The same problem is with "Problems by severity" widget and Problems page.