remote branches can't be bound

[Martin Pool]

RemoteBranch.bind raises UpgradeRequired. I suppose binding remote branches is not urgently needed but is there any good reason why it can't be done?

[Martin Pool (mbp)]

I tried naively just doing

    @needs_write_lock
    def bind(self, other):
        self._ensure_real()
        return self._real_branch.bind(other)

however, this causes the hooks to be invoked with the _real_branch, which is wrong (and fortunately is caught by hook tests.)