From: Shing Wai Chan <shing.wai.chan_at_oracle.com>
Date: Fri, 02 Nov 2012 16:11:25 -0700

As mentioned in SERVLET_SPEC-17, we would like to clarify the behavior
when an AsyncListener throws an exception.
I suggest that if #onStartAsync, #onComplete and #onTimeout have
failures, then #onError should be called.
Then it will give a chance for the listener to clean up resources.
If #onError has an error, then we should logged the exception and mark
the request in error state.
Any comments?

Shing Wai Chan