Comment 1 for bug 1820325

Following https://serverfault.com/questions/379714/unknown-unsupported-storage-engine-innodb-mysql-ubuntu, I removed /var/lib/mysql/ib_logfile0 and /var/lib/mysql/ib_logfile1, which allowed the service to start. There are various bad looking logs, e.g.

[Warning] InnoDB: Table mysql/innodb_index_stats has length mismatch in the column name table_name. Please run mysql_upgrade

This is clearly not the right course of action, but does show what is blocking the startup.

We also see these messages, suggesting we need to run mysql_upgrade:

[Warning] InnoDB: Table mysql/innodb_table_stats has length mismatch in the column name table_name. Please run mysql_upgrade