Docserver: Fix broken redirect on code.google.com/chrome/

chrome/common/extensions/docs/server2/servlet.py

 # Copyright 2013 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.
 
 
 class RequestHeaders(object):
   '''A custom dictionary impementation for headers which ignores the case
   of requests, since different HTTP libraries seem to mangle them.
   '''
   def __init__(self, dict_):
@@ skipping 14 matching lines @@
 
 class Request(object):
   '''Request data.
   '''
   def __init__(self, path, host, headers):
     self.path = path.lstrip('/')
     self.host = host.rstrip('/')
     self.headers = RequestHeaders(headers)
 
   @staticmethod
-  def ForTest(path, host='http://developer.chrome.com', headers=None):
-    return Request(path, host, headers or {})
+  def ForTest(path, host=None, headers=None):
+    return Request(path, host or 'http://developer.chrome.com', headers or {})
 
   def __repr__(self):
     return 'Request(path=%s, host=%s, headers=%s)' % (
         self.path, self.host, self.headers)
 
   def __str__(self):
     return repr(self)
 
 class _ContentBuilder(object):
   '''Builds the response content.
@@ skipping 103 matching lines @@
     return repr(self)
 
 class Servlet(object):
   def __init__(self, request):
     self._request = request
 
   def Get(self):
     '''Returns a Response.
     '''
     raise NotImplemented()