context: audit paths before clearing unknown files and dirs

Fix regression introduced in D785.

In some circumstances, context.clearunknown can be called before the path is
audited. Audit the path before deleting any conflicting files.

Differential Revision: https://phab.mercurial-scm.org/D1157

mercurial/context.py

@@ -1946,6 +1946,7 b' class workingfilectx(committablefilectx)'
         """
         wvfs = self._repo.wvfs
         f = self._path
+        wvfs.audit(f)
         if wvfs.isdir(f) and not wvfs.islink(f):
             wvfs.rmtree(f, forcibly=True)
         for p in reversed(list(util.finddirs(f))):

tests/test-audit-path.t

@@ -125,8 +125,7 b' attack ../test'
   abort: path contains illegal component: ../test (glob)
   [255]
   $ cat ../test/file
-  cat: ../test/file: No such file or directory
-  [1]
+  data
 
 attack /tmp/test