filter: `updatebranchcache` during `addchangegroup` instead of after lock The forced recomputation of the branch cache was introduced by `ee317dbfb9d0`. Back there, `addchangegroup` did not handle any lock logic. Later `ee1ed6afac21` introduced lock logic to `addchangegroup`. Its description does not explain why the `updatebranchcache` call is made outside locking. I believe that the lock was released there because it fit well with the transaction release already in the code. Finally `926a06f7a353` moved all "unlocked" code of `addchangegroup` to an `repo._afterlock` callback. I do not think that the call to `updatebranchcache()` requires to be done outside locking. That may even be a bad idea to do so. Bringing this call back in the `addchangegroup` function makes the flow simpler and eases the following up changelog level filtering business.