Add an assert to ensure UTF-8 locale when handling file paths.

appengine/components/tool_support/local_app.py

 #!/usr/bin/env python
 # Copyright 2014 The Swarming Authors. All rights reserved.
 # Use of this source code is governed by the Apache v2.0 license that can be
 # found in the LICENSE file.
 
 """Tools to control application running via dev_appserver.py.
 
 Useful for smoke and integration tests.
 """
 
 import collections
 import cookielib
 import ctypes
 import json
 import logging
 import os
 import shutil
 import socket
 import subprocess
 import sys
 import tempfile
 import time
 import urllib2
 
 from . import gae_sdk_utils
 
+from utils import file_path
+
 
 def terminate_with_parent():
   """Sets up current process to receive SIGTERM when its parent dies.
 
   Works on Linux only. On Win and Mac it's noop.
   """
   try:
     libc = ctypes.CDLL('libc.so.6')
   except OSError:
     return
@@ skipping 164 matching lines @@
         while self._proc.poll() is None and time.time() < deadline:
           time.sleep(0.05)
         exit_code = self._proc.poll()
         if exit_code is None:
           logging.error('Leaking PID %d', self._proc.pid)
     finally:
       with open(os.path.join(self._temp_root, 'dev_appserver.log'), 'r') as f:
         self._log = f.read()
       if not leak:
         try:
-          shutil.rmtree(self._temp_root)
+          file_path.rmtree(self._temp_root)
         except OSError as e:
           # Log but ignore it to not mask other errors.
           print >> sys.stderr, str(e)
       self._client = None
       self._port = None
       self._proc = None
       self._serving = False
       self._temp_root = None
     return exit_code
 
@@ skipping 71 matching lines @@
 
     It only works with apps that use 'auth' component.
     """
     if self._xsrf_token is None:
       resp = self.json_request(
           '/auth/api/v1/accounts/self/xsrf_token',
           body={},
           headers={'X-XSRF-Token-Request': '1'})
       self._xsrf_token = resp.body['xsrf_token'].encode('ascii')
     return self._xsrf_token