* Add `PerSessionKeyBackupDownloader.isKeyBackupDownloadConfigured()`
* Add new `RustBackupManager.getServerBackupInfo`
... and a convenience method in PerSessionKeyBackupDownloader to access it.
* Crypto.spec: move `useRealTimers` to global `afterEach`
... so that we don't need to remember to do it everywhere.
* Use fake timers for UTD error code tests
This doesn't have any effect on the tests, but *does* stop jest from hanging
when you run the tests in in-band mode. It shouldn't *really* be needed, but
using fake timers gives more reproducible tests, and I don't have the
time/patience to debug why it is needed.
* Use new error codes for UTDs from historical events
Richard van der Hoff
c30e498013