In GNOME 3.12, going to "Date and Time" under 'Settings' and selecting "Automatic Date and Time" appears to install an initscript /etc/init.d/busybox-ntpd, which may not start at login due to it not depending on a network interface being available.

Right now, the Funtoo networking scripts don't provide a mechanism to depend on a generic "working internet connection". Possibly, this could be added – interfaces with gateways as well as networkmanager and dhcpcd could provide "netif-active" or something like that.