make version of ts_mon compatible with appengine

infra_libs/httplib2_utils.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 json
 import logging
 import os
 import time
 
 import httplib2
 import oauth2client.client
 
-from infra_libs import http_metrics
+from infra_libs.ts_mon.common import http_metrics
 
 DEFAULT_SCOPES = ['email']
 
 # This is part of the API.
 # TODO: this is linux-specific, make it multi-platform.
 SERVICE_ACCOUNTS_CREDS_ROOT = '/creds/service_accounts'
 
 
 class AuthError(Exception):
   pass
@@ skipping 144 matching lines @@
     duration_msec = (self.time_fn() - start_time) * 1000
 
     http_metrics.response_bytes.add(len(content), fields=self.fields)
     http_metrics.durations.add(duration_msec, fields=self.fields)
 
     status_fields = {'status': response.status}
     status_fields.update(self.fields)
     http_metrics.response_status.increment(fields=status_fields)
 
     return response, content