What is the relationship between Grocon and construction in the context of the input sentence. Choose an answer from: product/material produced; manufacturer; distributed by; industry; position held; original broadcaster; owned by; founded by; distribution format; headquarters location; stock exchange; currency; parent organization; chief executive officer; director/manager; owner of; operator; member of; employer; chairperson; platform; subsidiary; legal form; publisher; developer; brand; business division; location of formation; creator.

The revival of the commission is part of a campaign against the militant construction union by the government, which includes support for developer Grocon and building materials group Boral in their battles with the union and the Heydon royal commission.

Answer: industry