Move ProxyConfigService construction onto the IO thread.

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 f612fa56a61f9e4d043da2a31e1daf151306c072..f1cb95fe8f1a11f970b8390100ba0b18ce595bd2 100644
--- a/content/shell/shell_url_request_context_getter.cc
+++ b/content/shell/shell_url_request_context_getter.cc
@@ -39,20 +39,16 @@ ShellURLRequestContextGetter::ShellURLRequestContextGetter(
       base_path_(base_path),
       io_loop_(io_loop),
       file_loop_(file_loop) {
-  // Must first be created on the UI thread.
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-  // We must create the proxy config service on the UI loop on Linux because it
-  // must synchronously run on the glib message loop. This will be passed to
-  // the URLRequestContextStorage on the IO thread in GetURLRequestContext().
-  proxy_config_service_.reset(
-      net::ProxyService::CreateSystemProxyConfigService(
-          io_loop_->message_loop_proxy(), file_loop_));
 }
 
 ShellURLRequestContextGetter::~ShellURLRequestContextGetter() {
 }
 
+void ShellURLRequestContextGetter::StartTearDown() {
+  if (url_request_context_.get())
+    url_request_context_->proxy_service()->StartTearDown();
+}
+
 net::URLRequestContext* ShellURLRequestContextGetter::GetURLRequestContext() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
@@ -79,9 +75,11 @@ net::URLRequestContext* ShellURLRequestContextGetter::GetURLRequestContext() {
     // TODO(jam): use v8 if possible, look at chrome code.
     storage_->set_proxy_service(
         net::ProxyService::CreateUsingSystemProxyResolver(
-        proxy_config_service_.release(),
-        0,
-        NULL));
+            net::ProxyService::CreateSystemProxyConfigService(
+                BrowserThread::GetMessageLoopProxyForThread(BrowserThread::UI),
+                file_loop_),
+            0,
+            NULL));
     storage_->set_ssl_config_service(new net::SSLConfigServiceDefaults);
     storage_->set_http_auth_handler_factory(
         net::HttpAuthHandlerFactory::CreateDefault(