HPCC-11189 onContentChanged is no longer needed

Fixes HPCC-11189

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>

Conflicts:
	esp/src/eclwatch/ESPUtil.js

Conflicts:
	esp/src/eclwatch/ESPUtil.js
Merge pull request #5678 from GordonSmith/HPCC-11189

HPCC-11189 onContentChanged is no longer needed

Reviewed-By: Kevin Wang <kevin.wang@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>