[Findit] Re-org code.

appengine/findit/waterfall/send_notification_for_culprit_pipeline.py

 # Copyright 2016 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.
 
 from datetime import datetime
 import logging
 import textwrap
 
 from google.appengine.ext import ndb
 
 from common.http_client_appengine import HttpClientAppengine as HttpClient
 from common.pipeline_wrapper import BasePipeline
-from common.rietveld import Rietveld
+from infra_api_clients.codereview.rietveld import Rietveld
 from lib import time_util
 from lib.gitiles.gitiles_repository import GitilesRepository
 from model import analysis_status as status
 from model.wf_analysis import WfAnalysis
 from model.wf_culprit import WfCulprit
 from waterfall import build_util
 from waterfall import waterfall_config
 
 
 def _AdditionalCriteriaAllPassed(additional_criteria):
@@ skipping 108 matching lines @@
         'within_time_limit': within_time_limit
     }
 
     if not _ShouldSendNotification(
       master_name, builder_name, build_number, repo_name,
       revision, commit_position, build_num_threshold, additional_criteria,
       send_notification_right_now):
       return False
     return _SendNotificationForCulprit(
         repo_name, revision, commit_position, code_review_url)