Any code that accesses rev_text_id and ar_text_id fields is unable to make use of MCR. In order to enable for MCR support, all references to these fields have to be removed from the code. They should be replaced with RevisionStore::getQueryInfo(), RevisionStore::newRevisionFromRow(), and RevisionRecord::getContent().
As a corollary, all references to text.old_id should be removed as well. If rev_text_id and ar_text_id are no longer there, there is no need to reference text.old_id (except in SqlBlobStore). A search for uses of the _text_id suffix in may be helpful to find code that needs fixing.
DOD: This task should be considered done when any code referencing rev_text_id or ar_text_id has either been removed or is gated on the MCR schema migration stage, in core and all extensions deployed by Wikimedia, as well as extensions bundled with MediaWiki releases. Other extensions and external tools may be left to be updated later.
Extensions to fix:
- Translate (T228675)
- EntitySchema (test only)
- Flow (maintenance script)
- ReplaceText (bundeled)
- WikimediaMaintenance (used internally by wmf)