private static boolean areRowIdsProjected(VectorizedRowBatchCtx rbCtx) {
    //The query needs ROW__ID: maybe explicitly asked, maybe it's part of
    // Update/Delete statement.
    //Either way, we need to decorate "original" rows with row__id
    return isVirtualColumnProjected(rbCtx, VirtualColumn.ROWID);
  }
Does this reader need to decorate rows with ROW__IDs (for "original" reads).
Even if ROW__ID is not projected you still need to decorate the rows with them to see if
any of the delete events apply.
ql/src/java/org/apache/hadoop/hive/ql/io/orc/VectorizedOrcAcidRowBatchReader.java