Revert "fix headless exception (#3532)"
Revert "fix headless exception (#3532)"

This reverts commit d404f688a5ea58fbaff1522894e786b3fc8cb3c5.

mbenguig/scheduling,ShatalovYaroslav/scheduling,ow2-proactive/scheduling,ShatalovYaroslav/scheduling,mbenguig/scheduling,ow2-proactive/scheduling,fviale/scheduling,mbenguig/scheduling,ShatalovYaroslav/scheduling,mbenguig/scheduling,mbenguig/scheduling,ow2-proactive/scheduling,fviale/scheduling,ShatalovYaroslav/scheduling,ow2-proactive/scheduling,ow2-proactive/scheduling,fviale/scheduling,ShatalovYaroslav/scheduling,ShatalovYaroslav/scheduling,ShatalovYaroslav/scheduling,fviale/scheduling,ow2-proactive/scheduling,fviale/scheduling,fviale/scheduling,fviale/scheduling,mbenguig/scheduling,ow2-proactive/scheduling,mbenguig/scheduling