[Findit] Re-org code.

appengine/findit/common/http_client_appengine.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 json
 import logging
 
 from google.appengine.api import urlfetch
 
 from common import auth_util
-from common.retry_http_client import RetryHttpClient
+from libs.http.retry_http_client import RetryHttpClient
 
 
 # TODO(katesonia): Move this to config.
 _INTERNAL_HOSTS_TO_SCOPES = {
     'https://chrome-internal.googlesource.com/': (
         'https://www.googleapis.com/auth/gerritcodereview'),
     'https://codereview.chromium.org/': (
         'https://www.googleapis.com/auth/userinfo.email'),
 }
 
@@ skipping 43 matching lines @@
     return result.status_code, result.content
 
   def _Get(self, url, timeout, headers):
     return self._SendRequest(url, urlfetch.GET, None, timeout, headers)
 
   def _Post(self, url, data, timeout, headers):
     return self._SendRequest(url, urlfetch.POST, data, timeout, headers)
 
   def _Put(self, url, data, timeout, headers):
     return self._SendRequest(url, urlfetch.PUT, data, timeout, headers)