Make the proxy server HostPortPair available in document_state so that

content/browser/loader/resource_loader.cc

 // Copyright (c) 2012 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.
 
 #include "content/browser/loader/resource_loader.h"
 
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/time/time.h"
@@ skipping 37 matching lines @@
   request->GetCharset(&response->head.charset);
   response->head.content_length = request->GetExpectedContentSize();
   request->GetMimeType(&response->head.mime_type);
   net::HttpResponseInfo response_info = request->response_info();
   response->head.was_fetched_via_spdy = response_info.was_fetched_via_spdy;
   response->head.was_npn_negotiated = response_info.was_npn_negotiated;
   response->head.npn_negotiated_protocol =
       response_info.npn_negotiated_protocol;
   response->head.connection_info = response_info.connection_info;
   response->head.was_fetched_via_proxy = request->was_fetched_via_proxy();
+  response->head.proxy_server = response_info.proxy_server;
   response->head.socket_address = request->GetSocketAddress();
   if (ServiceWorkerRequestHandler* handler =
           ServiceWorkerRequestHandler::GetHandler(request)) {
     handler->GetExtraResponseInfo(
         &response->head.was_fetched_via_service_worker,
         &response->head.was_fallback_required_by_service_worker,
         &response->head.original_url_via_service_worker,
         &response->head.response_type_via_service_worker,
         &response->head.service_worker_fetch_start,
         &response->head.service_worker_fetch_ready,
@@ skipping 638 matching lines @@
     UMA_HISTOGRAM_ENUMERATION("Net.Prefetch.Pattern", status, STATUS_MAX);
   }
 }
 
 void ResourceLoader::ContinueWithCertificate(net::X509Certificate* cert) {
   ssl_client_auth_handler_.reset();
   request_->ContinueWithCertificate(cert);
 }
 
 }  // namespace content