Emmanuele Bassi authored Aug 25, 2020 and aeldemery committed Aug 28, 2020

We cannot pass all the data we pass to the virtual function, because the
types are private, but the class and the signal are public API.

The signal is just a notification, so we can decouple the virtual
function (which stays the same, for internal types that implement the
ATContext API contract) from the signal.