revlog: compute length of compressed deltas along with chain length
In upcoming patches to the revlog, we're going to split up the notions of
bounding I/O and bounding CPU.
revlog: store fulltext when compressed delta is bigger than it
This is a very silly case and not particularly likely to happen in the wild,
but it turns out we can hit it in a couple of places. As we tune the storage
parameters we're likely to hit more such cases.
The affected test cases all have smaller revlogs now.