[PATCH 4 of 6 V1] lock: use util.unlink (issue2537)

[Adrian Buehlmann]

# HG changeset patch
# User Adrian Buehlmann <adrian at cadifra.com>
# Date 1294751416 -3600
# Node ID 205f5b4dfe515987cf29eb921f6d87d3e4076c62
# Parent  6cdc45c780e121737a5663fc078bd093b1c64e80
lock: use util.unlink (issue2537)

diff --git a/mercurial/lock.py b/mercurial/lock.py
--- a/mercurial/lock.py
+++ b/mercurial/lock.py
@@ -113,7 +113,7 @@ class lock(object):
         # held, or can race and break valid lock.
         try:
             l = lock(self.f + '.break', timeout=0)
-            os.unlink(self.f)
+            util.unlink(self.f)
             l.release()
         except error.LockError:
             return locker
@@ -126,7 +126,7 @@ class lock(object):
             if self.releasefn:
                 self.releasefn()
             try:
-                os.unlink(self.f)
+                util.unlink(self.f)
             except OSError:
                 pass