R1:8a2863e3f7f8

Change the "can see remote address?" policy to "is administrator?" everywhere

Summary:
Depends on D18970. Ref T13049. Currently, the policy for viewing remote addresses is:

- In activity logs: administrators.
- In push and pull logs: users who can edit the corresponding repository.

This sort of makes sense, but is also sort of weird. Particularly, I think it's kind of hard to understand and predict, and hard to guess that this is the behavior we implement. The actual implementation is complex, too.