Summary:
Ref T4896. This is substantially similar to D8196.
Migrate the comment text out of the `audit_comment` table and into the `audit_transaction_comment` table. Do double reads on `PhabricatorAuditComment` so the APIs aren't disturbed. The old table is still updated.
Test Plan:
- Before applying migration, cleared cache and browsed around. Things looked fine, except no comment text.
- Applied migration.
- Cleared cache, browsed around, saw all my old comments.
- Added some new comments.
- Spot checked migrated and new rows in database.
Reviewers: btrahan, joshuaspence
Reviewed By: joshuaspence
Subscribers: epriestley
Maniphest Tasks: T4896
Differential Revision: https://secure.phabricator.com/D10020
