Fix update 7002 failure on current MySQL

Problem/Motivation

Since MySQL 5.7, the Drupal 7 code for adding a serial field to a table does not work. A fix has been available but has been blocked for years. #2615496: A serial/primary key field can not be added to an existing table for some databases →

Steps to reproduce

Run update 7002 on a database that has records in the node_revision_states_history table.

Proposed resolution

Create an int field and change it to a serial field.