[Cronet] Allow experimenting with Chrome's internal DNS resolver.

components/cronet/android/url_request_context_adapter.cc

 // 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.
 
 #include "components/cronet/android/url_request_context_adapter.h"
 
 #include <limits>
 
 #include "base/bind.h"
 #include "base/files/file_util.h"
@@ skipping 132 matching lines @@
   // TODO(mef): Remove this work around for crbug.com/543366 once it is fixed.
   net::URLRequestContextBuilder::HttpNetworkSessionParams
       custom_http_network_session_params;
   custom_http_network_session_params.use_alternative_services = false;
   context_builder.set_http_network_session_params(
       custom_http_network_session_params);
 
   context_builder.set_network_delegate(
       make_scoped_ptr(new BasicNetworkDelegate()));
   context_builder.set_proxy_config_service(proxy_config_service_.Pass());
-  config_->ConfigureURLRequestContextBuilder(&context_builder);
+  config_->ConfigureURLRequestContextBuilder(&context_builder, nullptr);
 
   context_ = context_builder.Build().Pass();
 
   if (config_->enable_sdch) {
     DCHECK(context_->sdch_manager());
     sdch_owner_.reset(
         new net::SdchOwner(context_->sdch_manager(), context_.get()));
   }
 
   // Currently (circa M39) enabling QUIC requires setting probability threshold.
@@ skipping 149 matching lines @@
     write_to_file_observer_.reset();
   }
 }
 
 void NetLogObserver::OnAddEntry(const net::NetLog::Entry& entry) {
   VLOG(2) << "Net log entry: type=" << entry.type()
           << ", source=" << entry.source().type << ", phase=" << entry.phase();
 }
 
 }  // namespace cronet