R1:dccd799b1b44

Move many "reviewers" readers to new storage

Summary:
Ref T10967.

When we query for revisions with particular reviewers, use the new table to drive the query.

When we load revisions for use in the application, also use the new table to drive the query.

This doesn't convert everything: there's some old `loadRelationships()` stuff still using the old table. But this moves the major stuff over.

(This also changes the icon for "commented" from a question mark to a speech bubble.)

Test Plan:
- Viewed…