Major Description
As of KAFKA-8199, the suppression buffers have to track the "prior value" in addition to the "old" and "new" values for each record, to support transparent downstream views.
In many cases, the prior value is actually the same as the old value, and we could avoid storing it separately. The challenge is that the old and new values are already serialized into a common array (as a Change via the FullChangeSerde), so the "prior" value would actually be a slice on the underlying array. But, of course, Java does not have array slices.
To get around this, we either need to switch to ByteBuffers (which support slices) or break apart the serialized Change into just serialized old and new values.