Martin Geisler <mg@aragost.com> [Tue, 24 May 2011 16:12:01 +0200] rev 14419
wireproto: do not hash when heads == ['force']
Changeset 88f0e41d8802 introduced the unbundlehash capability and
unconditionally hashed the heads on the client side. By mistake, the
heads were also cased in the heads == ['force'] case.