Use new common utils where possible.

slave/skia_slave_scripts/check_for_regressions.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.
 
 """ Check for regressions in bench data. """
 
 from build_step import BuildStep
-from utils import shell_utils
+from py.utils import shell_utils
 
 import builder_name_schema
 import os
 import sys
 
 
 class CheckForRegressions(BuildStep):
   def __init__(self, timeout=600, no_output_timeout=600, **kwargs):
     super(CheckForRegressions, self).__init__(
         timeout=timeout,
@@ skipping 21 matching lines @@
 
     shell_utils.run(cmd)
 
   def _Run(self):
     if self._perf_data_dir:
       self._RunInternal('25th')
 
 
 if '__main__' == __name__:
   sys.exit(BuildStep.RunBuildStep(CheckForRegressions))