Wrong action from supervisor strategy when running multiple tests

[rogeralsing]

The actorStartedException succeeds when running in isolation. But when running together with the full testsuite, it fails.

I can see that we are getting the wrong system message in the ActorContext at a point. The handleFailure of the OneForOneStrategy is the caller, and it seems to be passing the message.

Not clear what causes this. Concurrency issues in a concurrency lib are the best :-/