fix fromsql for domains

[zacknewman]

Fixes #1188.

[sfackler]

Can you add a test for the case that was failing before this fix?

[zacknewman]

Added a test.

[zacknewman]

@sfackler, ping. Is it possible this gets merged? Currently one has to maintain their own fork that isn't affected by this bug, manually implement FromSql instead of deriveing it, or live without the ability to construct certain types in PostgreSQL (which ideally would be documented at least). Can I improve the PR somehow?

[ZakSingh]

Would really love to see this merged! Ran into this issue recently.

[paolobarbolini]

sqlx ended up merging the PR mentioned in #1188 (comment), and their fix is very similar to yours https://github.com/launchbadge/sqlx/blob/c52e129e8341c46b2ea5c9b912e1af665be1ef83/sqlx-postgres/src/type_info.rs#L1039-L1050. They haven't tagged a release yet, so it hasn't really been tested in the wild, but the fix looks right so I'm merging it.