Fix allow 'implementing your own resolver' to work.

When the ListenersInvoker class is initialized, the Entity Listener Resolver is instantiated within the constructor and stored as a property onto the ListenersInvoker class; this doesn't work. When a User implements and set his or her own Entity Listener Resolver, it is ignored because because the Entity Listener Resolver has already been stored onto the class.

Instead of calling getEntityListenerResolver within the constructor, getEntityListenerResolver is called when resolving the User's EntityListenerResolver.