Another rmtree-related test failure

gistfile1.txt

=================================== FAILURES ===================================
________________________ TestIntegration.test_filenames ________________________
self = <tests.test_unit_integration.TestIntegration testMethod=test_filenames>
    def tearDown(self):
>       common.shared_teardown()
tests/test_unit_integration.py:81: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
tests/common.py:74: in shared_teardown
    clean_root()
tests/common.py:13: in clean_root
    shutil.rmtree(config.SECUREDROP_DATA_ROOT)
/usr/lib/python2.7/shutil.py:254: in rmtree
    onerror(os.rmdir, path, sys.exc_info())
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
path = '/tmp/securedrop', ignore_errors = False
onerror = <function onerror at 0x3b80c80>
    def rmtree(path, ignore_errors=False, onerror=None):
        """Recursively delete a directory tree.
    
        If ignore_errors is set, errors are ignored; otherwise, if onerror
        is set, it is called to handle the error with arguments (func,
        path, exc_info) where func is os.listdir, os.remove, or os.rmdir;
        path is the argument to that function that caused it to fail; and
        exc_info is a tuple returned by sys.exc_info().  If ignore_errors
        is false and onerror is None, an exception is raised.
    
        """
        if ignore_errors:
            def onerror(*args):
                pass
        elif onerror is None:
            def onerror(*args):
                raise
        try:
            if os.path.islink(path):
                # symlinks to directories are forbidden, see bug #1669
                raise OSError("Cannot call rmtree on a symbolic link")
        except OSError:
            onerror(os.path.islink, path, sys.exc_info())
            # can't continue even if onerror hook returns
            return
        names = []
        try:
            names = os.listdir(path)
        except os.error, err:
            onerror(os.listdir, path, sys.exc_info())
        for name in names:
            fullname = os.path.join(path, name)
            try:
                mode = os.lstat(fullname).st_mode
            except os.error:
                mode = 0
            if stat.S_ISDIR(mode):
                rmtree(fullname, ignore_errors, onerror)
            else:
                try:
                    os.remove(fullname)
                except os.error, err:
                    onerror(os.remove, fullname, sys.exc_info())
        try:
>           os.rmdir(path)
E           OSError: [Errno 39] Directory not empty: '/tmp/securedrop'
/usr/lib/python2.7/shutil.py:252: OSError
===================== 1 failed, 43 passed in 30.72 seconds =====================