Description of problem:
When setting /org/gnome/login-screen/disable-user-list = true in dconf for gdm, TimedLogin settings in /etc/gdm/custom.conf are ignored at gdm start.

Version-Release number of selected component (if applicable):
3.28.2-10

How reproducible:
100%

Steps to Reproduce:
1 Run "systemctl isolate multi-user.target" as root to switch to multiuser mode and log in.
2. Add the following lines in the [daemon] section of /etc/gdm/custom.conf:
TimedLoginEnable=true
TimedLogin=<user>
TimedLoginDelay=10

3. Add the following to /etc/dconf/profile/gdm (if not there already):
user-db:user
system-db:gdm
file-db:/usr/share/gdm/greeter-dconf-defaults

4. Create /etc/dconf/db/gdm.d/01-custom-gdm-settings with the following lines:
[org/gnome/login-screen]
disable-user-list=true

5. Run "dconf update" as root to rebuild the dconf database.
6. Run "systemctl isolate graphical.target" as root to restart the graphical subsystem.

Actual results:
System remains at the GDM login prompt after 10 seconds.

Expected results:
System should log in automatically as <user>, with <user>'s graphical session, after 10 seconds.