When launching PNaCl helper nexes, explicitly disable IRT loading.

chrome/browser/renderer_host/chrome_render_message_filter.cc

Index: chrome/browser/renderer_host/chrome_render_message_filter.cc
diff --git a/chrome/browser/renderer_host/chrome_render_message_filter.cc b/chrome/browser/renderer_host/chrome_render_message_filter.cc
index ebae5760d03d6c647027d5ea5d5814cb890186aa..fb71de3924049599945d34978c4a849a509c5324 100644
--- a/chrome/browser/renderer_host/chrome_render_message_filter.cc
+++ b/chrome/browser/renderer_host/chrome_render_message_filter.cc
@@ -176,12 +176,14 @@ net::HostResolver* ChromeRenderMessageFilter::GetHostResolver() {
 void ChromeRenderMessageFilter::OnLaunchNaCl(const GURL& manifest_url,
                                              int render_view_id,
                                              uint32 permission_bits,
+                                             bool uses_irt,
                                              int socket_count,
                                              IPC::Message* reply_msg) {
   NaClProcessHost* host = new NaClProcessHost(manifest_url,
                                               render_view_id,
                                               permission_bits,
-                                              off_the_record_);
+                                              off_the_record_,
+                                              uses_irt);
   host->Launch(this, socket_count, reply_msg, extension_info_map_);
 }