Job does not quit when task shutdown is requested (when using ThreadJobFactory)

I have just started to try out Samza 0.10 by using the SNAPSHOT version on Apache repository and I'm running into a shutdown issue for a job which works fine on 0.9.1.

This is the job: https://gist.github.com/kishorenc/89eb18276c51b1478a18

I have not tried it yet on YARN, but when thread factory is used (for local development), this job just hangs without quitting even when a `taskCoordinator.shutdown(RequestScope.CURRENT_TASK)` is issued.

I have also included the jstack dump on the gist.