This reverts commit 8b2208fd9a, reversing
changes made to 2db6b12b78.
Unfortunately, this is rather tricky code. We've found several issues so
far and, while we've fixed a few, there are outstanding issues that
would require complex fixes we don't have time to tackle right now.
Luckily, this code isn't actually needed by the main Filecoin chain
which relies on consensus fault reporting to handle equivocation. So we
can just try again later.
bb5ba64cca