Provide mutable members of UrlRequestContext via pure-virtual interface

chrome/browser/profiles/off_the_record_profile_io_data.cc

Index: chrome/browser/profiles/off_the_record_profile_io_data.cc
diff --git a/chrome/browser/profiles/off_the_record_profile_io_data.cc b/chrome/browser/profiles/off_the_record_profile_io_data.cc
index 0bdf74d89832b1318b0042906c55d826ad55c3de..2b9608f67e933d06cd6788a1507a2521910562d1 100644
--- a/chrome/browser/profiles/off_the_record_profile_io_data.cc
+++ b/chrome/browser/profiles/off_the_record_profile_io_data.cc
@@ -13,6 +13,7 @@
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/io_thread.h"
 #include "chrome/browser/net/about_protocol_handler.h"
+#include "chrome/browser/net/basic_http_user_agent_settings.h"
 #include "chrome/browser/net/chrome_net_log.h"
 #include "chrome/browser/net/chrome_url_request_context.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ -165,6 +166,12 @@ void OffTheRecordProfileIOData::LazyInitializeInternal(
   IOThread* const io_thread = profile_params->io_thread;
   IOThread::Globals* const io_thread_globals = io_thread->globals();
 
+  http_user_agent_settings_.reset(new BasicHttpUserAgentSettings(
+      profile_params->accept_language, profile_params->accept_charset));
+  main_context->set_http_user_agent_settings(http_user_agent_settings_.get());
+  extensions_context->set_http_user_agent_settings(
+      http_user_agent_settings_.get());
+
   ApplyProfileParamsToContext(main_context);
   ApplyProfileParamsToContext(extensions_context);