make version of ts_mon compatible with appengine

appengine/sheriff_o_matic/user_prefs.py

 # Copyright 2014 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 calendar
-import contextlib
-import datetime
-import datetime_encoder
 import json
 import logging
-import os
-import sys
+import utils
 import webapp2
-import zlib
 
-import cloudstorage as gcs
-
-from google.appengine.api import app_identity
-from google.appengine.api import memcache
 from google.appengine.api import users
-from google.appengine.datastore import datastore_query
 from google.appengine.ext import ndb
 
 from components import auth
 
 
 class UserPrefs(ndb.Model):
   user_id = ndb.StringProperty()
   use_uberchromegw = ndb.BooleanProperty()
   use_new_windows = ndb.BooleanProperty()
 
@@ skipping 42 matching lines @@
     if prefs_list:
       prefs = prefs_list[0]
 
     user_prefs.use_uberchromegw = prefs['use_uberchromegw']
     user_prefs.use_new_windows = prefs['use_new_windows']
     user_prefs.put()
 
 app = webapp2.WSGIApplication([
     ('/api/v1/prefs', UserPrefsHandler),
 ])