wireprotocol: use visibleheads as reference while unbundling (issue 3303)...
wireprotocol: use visibleheads as reference while unbundling (issue 3303)
The `repo` object here is *always* local. Using `repo.heads()` ensure we will
reject push if any secret changeset exists.
During discovery, `visibleheads` were sent to the peer. So we can only expect it
to send us `visibleheads` back. If any secret changeset exists::
visibleheads != repo.heads()
This fix server side part of issue 3303 when pushing over the wire.
