Fix run_isolated_smoke_test to work when /tmp is on a separate partition.

tests/run_isolated_smoke_test.py

 #!/usr/bin/env python
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import hashlib
 import json
 import logging
 import os
 import shutil
 import subprocess
 import sys
-import tempfile
 import unittest
 
 ROOT_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 sys.path.insert(0, ROOT_DIR)
 
 # Imported for the rmtree and get_as_zip_package functions.
 import run_isolated
 
 VERBOSE = False
 
@@ skipping 34 matching lines @@
     f.write(content)
 
 
 def write_json(filepath, data):
   with open(filepath, 'wb') as f:
     json.dump(data, f, sort_keys=True, indent=2)
 
 
 class RunSwarmStep(unittest.TestCase):
   def setUp(self):
-    self.tempdir = tempfile.mkdtemp(prefix='run_isolated_smoke_test')
+    self.tempdir = run_isolated.make_temp_dir(
+        'run_isolated_smoke_test', ROOT_DIR)
     logging.debug(self.tempdir)
     # run_isolated.zip executable package.
     self.run_isolated_zip = os.path.join(self.tempdir, 'run_isolated.zip')
     run_isolated.get_as_zip_package().zip_into_file(
         self.run_isolated_zip, compress=False)
     # The "source" hash table.
     self.table = os.path.join(self.tempdir, 'table')
     os.mkdir(self.table)
     # The slave-side cache.
     self.cache = os.path.join(self.tempdir, 'cache')
@@ skipping 96 matching lines @@
     if not VERBOSE:
       self.assertEqual('', err)
       self.assertEqual('Success\n', out, out)
     self.assertEqual(0, returncode)
     actual = list_files_tree(self.cache)
     self.assertEqual(sorted(set(expected)), actual)
 
   def test_download_isolated(self):
     out_dir = None
     try:
-      out_dir = tempfile.mkdtemp()
+      out_dir = run_isolated.make_temp_dir('run_isolated_smoke_test', ROOT_DIR)
 
       # Store the required files.
       self._store('file1.txt')
       self._store('repeated_files.py')
 
       # Loads an arbitrary .isolated on the file system.
       isolated = os.path.join(self.data_dir, 'download.isolated')
       out, err, returncode = self._run(
           self._generate_args_with_isolated(isolated) +
           ['--download', out_dir])
@@ skipping 118 matching lines @@
     self.assertEqual(0, returncode)
 
     self.assertEqual(os.stat(os.path.join(self.data_dir, 'file1.txt')).st_size,
                      os.stat(cached_file_path).st_size)
 
 
 if __name__ == '__main__':
   VERBOSE = '-v' in sys.argv
   logging.basicConfig(level=logging.DEBUG if VERBOSE else logging.ERROR)
   unittest.main()