get set del can throw sync and do not always return a promise

[minht11]

We noticed in Sentry reports that some users in Safari ios 18.4.1 were having errors [Can't find variable: indexedDB], but thats not what this issue is about.

Right now get set methods can throw sync:

console.log('Start')

// Simulate browser not supporting indexed db
delete globalThis.indexedDB

// Should not throw sync
get('any').catch(() => {
 console.log('Error')
})

console.log('End')

Reproduction https://jsfiddle.net/edtxc8k6/

Ideally get and other methods would always resolve promise, throwing sync is unexpected behavior.