Code review comment for lp:~verterok/ubuntuone-client/tritcask-win-compat

I have 2 tests failing in windows:

===============================================================================
[ERROR]
Traceback (most recent call last):
  File "E:\u1\client\review_tritcask-win-compat\tests\syncdaemon\test_tritcask.p
y", line 1406, in test_merge_mixed_dead_entries
    db = Tritcask(self.base_dir, auto_merge=False)
  File "E:\u1\client\review_tritcask-win-compat\ubuntuone\syncdaemon\tritcask.py
", line 590, in __init__
    self._rotate_and_merge()
  File "E:\u1\client\review_tritcask-win-compat\ubuntuone\syncdaemon\tritcask.py
", line 646, in _rotate_and_merge
    self.rotate(create_file=False)
  File "E:\u1\client\review_tritcask-win-compat\ubuntuone\syncdaemon\tritcask.py
", line 694, in rotate
    data_file = self.live_file.make_immutable()
  File "E:\u1\client\review_tritcask-win-compat\ubuntuone\syncdaemon\tritcask.py
", line 187, in make_immutable
    os.rename(self.filename, new_name)
exceptions.WindowsError: [Error 32] The process cannot access the file because i
t is being used by another process

tests.syncdaemon.test_tritcask.MergeTests.test_merge_mixed_dead_entries
===============================================================================
[ERROR]
Traceback (most recent call last):
  File "E:\u1\client\review_tritcask-win-compat\tests\syncdaemon\test_tritcask.p
y", line 323, in test_delete
    new_file.delete()
  File "E:\u1\client\review_tritcask-win-compat\ubuntuone\syncdaemon\tritcask.py
", line 398, in delete
    os.unlink(self.filename)
exceptions.WindowsError: [Error 32] The process cannot access the file because i
t is being used by another process: 'C:\\Temp\\5\\_trial_temp\\tmp\\tests.syncda
emon.test_tritcask\\TempDataFileTest\\test_delete\\data_dir\\1258630.tmp7u7m6a.t
ritcask-v1.data'

tests.syncdaemon.test_tritcask.TempDataFileTest.test_delete
-------------------------------------------------------------------------------

Can you please replace os.rename by the ubuntuone.platform.rename?