JCBC-230: Release Connection also on cancel()

This changeset properly releases the view connection also
on cancel(), not only on completed().

Change-Id: I6f2d5e83f4356db2e827b61098a94b4f7d9d6be0
Reviewed-on: http://review.couchbase.org/24343
Reviewed-by: Matt Ingenthron <matt@couchbase.com>
Tested-by: Michael Nitschinger <michael.nitschinger@couchbase.com>