Ideally, publish operations should act like this:

• The "Acting As" PHID is the identity PHID associated with the commit. If one does not exist, the acting as PHID is the Diffusion application.
• When we want to respect policies (Fixes Txxx), the acting user is the user associated with the identity, if one exists, or the omnipotent user if one does not.
• The "Acting User" in Herald is the acting user associated with the identity, if one exists, or the Diffusion application, if one does not.

Boneyard

• The git fetch change in D20421 may require an adjacent change to the two places where we call isWorkingCopyBare() before listing refs. I suspect we can now remove the special casing.
• From D20436, we should go dig up the actual wire-proto.c in Git and verify the discovered protocol matches the implemented protocol.