Accessor method for internal MP AbstractSubscriber mapListener

[brianoliver]

Would like to request the addition of a protected accessor method in the AbstractSubscriber class in MP for the following attribute:

/**

• The {@link MapListener}

that will be used to receive call back events

• (and new {@link Subscription}

state) from the cluster.
*/
private MapListener mapListener;

This would provide custom subscriber extensions with access to the Coherence mapListener used by MP subscribers internally by default.

[brianoliver]

Reported by alexserban

[brianoliver]

This issue was imported from JIRA COHINC-70