Provide mutable members of UrlRequestContext via pure-virtual interface

content/shell/shell_url_request_context_getter.cc

Index: content/shell/shell_url_request_context_getter.cc
diff --git a/content/shell/shell_url_request_context_getter.cc b/content/shell/shell_url_request_context_getter.cc
index 9300dc686ce190cfe90e0d8f0141f6befa3de64d..3c4cb1290fc86261bbc3b110c8646ba438a29609 100644
--- a/content/shell/shell_url_request_context_getter.cc
+++ b/content/shell/shell_url_request_context_getter.cc
@@ -8,6 +8,7 @@
 #include "base/logging.h"
 #include "base/string_number_conversions.h"
 #include "base/string_split.h"
+#include "base/string_util.h"
 #include "base/threading/worker_pool.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/common/content_switches.h"
@@ -24,6 +25,7 @@
 #include "net/http/http_network_session.h"
 #include "net/http/http_server_properties_impl.h"
 #include "net/proxy/proxy_service.h"
+#include "net/url_request/static_http_user_agent_settings.h"
 #include "net/url_request/url_request_context.h"
 #include "net/url_request/url_request_context_storage.h"
 #include "net/url_request/url_request_job_factory_impl.h"
@@ -68,8 +70,9 @@ net::URLRequestContext* ShellURLRequestContextGetter::GetURLRequestContext() {
     storage_->set_server_bound_cert_service(new net::ServerBoundCertService(
         new net::DefaultServerBoundCertStore(NULL),
         base::WorkerPool::GetTaskRunner(true)));
-    url_request_context_->set_accept_language("en-us,en");
-    url_request_context_->set_accept_charset("iso-8859-1,*,utf-8");
+    storage_->set_http_user_agent_settings(
+        new net::StaticHttpUserAgentSettings(
+            "en-us,en", "iso-8859-1,*,utf-8", EmptyString()));
 
     scoped_ptr<net::HostResolver> host_resolver(
         net::HostResolver::CreateDefaultResolver(NULL));