[Pod] Move Diffable and TableRowLogger to log.table pod.

Pre-requisite for moving TableLogBuffer to a pod.

For now, doesn't move the extension functions because TableLogBuffer
isn't in a pod yet.

Bug: 307607958
Flag: EXEMPT refactor
Test: m SystemUI-core
Change-Id: I09d73ddc23f4f0220d5f9eb5414ab7979c74fc9c