For some reason patches like https://git.opendaylight.org/gerrit/q/I9641f527bbc0cb92732f2e513cdd64cc6a837200 were not introduced to MD-SAL and thus have fallen off the wagon.

This was not caught before, because the first component to actually use these is Genius, who did their conversion at the very last moment and just skipped over the missing class. This would be fine, except the wiring is more complicated than people realize and they messed up their tests as a result.