Make MemoryDatabase Send + Sync

[artfuldev]

Description

We make the MemoryDatabase Send + Sync. This is required for language bindings generation using uniffi-rs and is a very small change.

Checklists

All Submissions:

• I've signed all my commits
• I followed the contribution guidelines
• I ran cargo fmt and cargo clippy before committing

[LLFourn]

This LGTM. I think the idea here is to make sure that if you Arc<Mutex<>> the in memory database it will be send + sync as expected. Am I right?

No idea why these resolver test failures are reappearing in our CI.

[artfuldev]

I'm not sure I understand the Arc<Mutex<>> part. The only way to make it automatically Send + Sync is to ensure the inner-most contained type Box<dyn Any> is also Send + Sync - that was the only violation, so I added the trait constraint there.

[artfuldev]

No idea why these resolver test failures are reappearing in our CI.

Is this something to be fixed by me?

[LLFourn]

Is this something to be fixed by me?

Nah we should fix this.

[afilini]

The issue should be fixed now, you can try rebasing on the latest master

[notmandatory]

ACK 59f795f.