R1:48a34eced28d

Prepare for InnoDB FULLTEXT support

Summary:
Ref T11741. This makes everything work if we switch to InnoDB, but never actually switches yet.

Since the default minimum word length (3) and stopword list (36 common English words) in InnoDB are generally pretty reasonable, I just didn't add any setup advice for them. I figure we're better off with simpler setup until we identify some real problem that the builtin stopwords create.

Test Plan: Swapped the `false` to `true`, ran `storage adjust`, got InnoDB…