In D8472#250668, @michal wrote:

Looks good, just some questions:

• would it make sense to make these methods more inline with others? So e.g. setPersistStorageItem getting PersistItem as an argument, or getPersistStorageItem returning PersistItem or null instead of string?

That's an alternative approach, but I would prefer to stick to the current one:

• this is key-value table, I would prefer to match other key-value APIs (see metadata)
• this should replace the previous storage engine, eg. localstorage, and those functions match that API better
• when we try to retrieve item at given key, I do not see a reason to return the object with key

• can we test these methods, and amend the test plan?

Yes! I tested this in D8557 where I change tests to use new API