Transition listener notifications must be executed separately and last for every controller ongoing transition

MSC API users can use and they use
ServiceListener transition notifications to detect
when controller has moved to another state.
While StabilityMonitor usage is safe for similar
scenarios this is not the case for ServiceListener transition
notifications which are executed concurrently
with other controller tasks.

To fix this problem we need to fire ServiceListener
transition notifications if and only if all scheduled
controller dependent/dependency tasks finished its execution.