R1:711f13660e54

Synchronize working copies before doing a "bypassCache" commit read

Summary:
Ref T4292. When the daemons make a query for repository information, we need to make sure the working copy on disk is up to date before we serve the response, since we might not have the inforamtion we need to respond otherwise.

We do this automatically for almost all Diffusion methods, but this particular method is a little unusual and does not get this check for free. Add this check.

Test Plan:
- Made this code throw.