localrepo: clear _filecache on rollback (issue3261) Files are being replaced by rollback but the corresponding data in localrepo isn't actually updated for things like bookmarks, phases, etc. Then when rollback is done, the cache is updated thinking it has the most up-to-date data, where in fact it is still pre-rollback. We clear _filecache to force everything to be recreated.

  $ hg init
  $ echo This is file a1 > a
  $ hg add a
  $ hg commit -m "commit #0"
  $ ls
  a
  $ echo This is file b1 > b
  $ hg add b
  $ hg commit -m "commit #1"
  $ hg co 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

B should disappear

  $ ls
  a