Migrate and merge logging_utils from swarming_bot into client/utils.

client/utils/logging_utils_test.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.
+# Copyright 2015 The Swarming Authors. All rights reserved.
+# Use of this source code is governed under the Apache License, Version 2.0 that
+# can be found in the LICENSE file.
 
 import logging
 import os
 import sys
 import tempfile
 import shutil
 import unittest
 import re
 
-# Import this first before manipulating sys.path to ensure it can load fine.
-import logging_utils
-
 ROOT_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
 sys.path.insert(0, ROOT_DIR)
 
+from utils import logging_utils
+
 import test_env
 test_env.setup_test_env()
 
 from depot_tools import auto_stub
 
 _LOG_HEADER = r'^%s \d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d\.\d\d\d: ' % os.getpid()
 
 
 class TestLoggingUtils(auto_stub.TestCase):
   def test_Capture(self):
@@ skipping 14 matching lines @@
         result = f.read()
     finally:
       shutil.rmtree(tmp_dir)
     # It'd be nice to figure out a way to ensure it's properly in UTC but it's
     # tricky to do reliably.
     self.assertTrue(re.match(_LOG_HEADER + 'DEBUG foo\n$', result), result)
 
 
 if __name__ == '__main__':
   unittest.main()