HPCC-9905 Remove unnecessary code from the master branch

The code that was required in 4.0.2 is already present in the base class
on the master branch so it can be removed.

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
Merge pull request #4785 from ghalliday/issue9905b

HPCC-9905 Remove unnecessary code from the master branch

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>