Comment 1 for bug 1479747

The OA API is designed in such a way that hiding this information is far from being a trivial task.
We are working on a new version of the API, which doesn't have these shortcomings. That will be the only accounts API provided with framework 15.10 and later.
Unfortunately, in order not to break compatibility for apps using older frameworks, we cannot simply remove the old API; if this bug is considered worth it, we can work on turning the old API into a wrapper for the new one, so that it will still continue working but it won't provide any info about the accounts which the application cannot access.