This works similar to the offline and shutdown procedure in EShell.
We broadcast a "load-accounts" EShell event with an EActivity. The
EActivity has a toggle reference which we use as a counting semaphore.
If another module needs to handle the event asynchronously, it should
reference the EActivity until its async operation completes, then drop
the reference. Once the signal handlers finish and only the toggle
reference remains, we then proceed with the Evolution Setup Assistant.
All of this is in preparation for GNOME Online Accounts integration.
For the moment, nothing listens for the "load-accounts" EShell event,
so there should be no change in Evolution Setup Assistant behavior.
Matthew Barnes
b8fab0371d