[Findit] Factoring the gitiles (etc) stuff out into its own directory

appengine/findit/waterfall/build_failure_analysis.py

 # Copyright 2015 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 collections
 import os
 import re
 
-from common.diff import ChangeType
-from common.git_repository import GitRepository
+from gitiles.diff import ChangeType
+from gitiles.git_repository import GitRepository
 from common.http_client_appengine import HttpClientAppengine as HttpClient
 from waterfall import waterfall_config
 from waterfall.failure_signal import FailureSignal
 
 
 def _IsSameFile(changed_src_file_path, file_path_in_log):
   """Guesses if the two files are the same.
 
   Args:
     changed_src_file_path (str): Full path of a file committed to git repo.
@@ skipping 706 matching lines @@
             continue
 
           step_analysis_result['suspected_cls'].append(
               CreateCLInfoDict(justification_dict, build_number,
                                change_logs[revision]))
 
     # TODO(stgao): sort CLs by score.
     analysis_result['failures'].append(step_analysis_result)
 
   return analysis_result