MB-20772: Catch errors during final flush of ssl pipe
MB-20772: Catch errors during final flush of ssl pipe

We need to extend the test framework with methods to inject
socket errors in order to create a unit test for this.

Change-Id: I29972db6de6de7c36730a72778792d55a9c71589
Reviewed-on: http://review.couchbase.org/67354
Reviewed-by: Daniel Owen <b3fc0e1a51f252986e60be7da121b74d3ac6845f@couchbase.com>
Reviewed-by: Jim Walker <1cd02e31b43620d7c664e038ca42a060d61727b9@couchbase.com>
Well-Formed: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Tested-by: buildbot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>

daverigby/kv_engine,daverigby/memcached,couchbase/memcached,daverigby/kv_engine,couchbase/memcached,couchbase/memcached,daverigby/kv_engine,daverigby/memcached,daverigby/memcached,couchbase/memcached,daverigby/memcached,daverigby/kv_engine