T184615 talks about removing rev_text_id in favor of the multi-slot architecture of MCR. We don't do much with the rev_text_id, but it is selected and propagated throughout our mediawiki history pipeline. So at the very least we need to change sqoops and refinery-source code. We can start this work immediately and park it for when this change is deployed. If we don't have it ready, the mediawiki history jobs will fail.