Revert "MB-12697 Serialize parse_json requests chunks per query context"

This reverts commit cede9fe0761aa36eec2488103485c7b985e08f77.

Change-Id: Ieee9ccf680b1e627c4d6e0d30377ca860040f7de
Reviewed-on: http://review.couchbase.org/43632
Reviewed-by: Harsha H S <hhs.couchbase@gmail.com>
Tested-by: buildbot <build@couchbase.com>
Reviewed-by: Nimish Gupta <nimish@couchbase.com>