Major Description
The AsyncUpdateCallback gets notified whenever an editor updates the index via indexUpdate(). After every 100 changes the callback checks the lease time and extends the lease if necessary. In combination with OAK-1968 and more than 100 index changes, this will likely lead to an async-lease update in a separate commit from within the commit editor. Because of the way how OAK-1056 was fixed, this commit is mixed with the surrounding commit and may lead to a conflict or otherwise fail the commit.