When launching PNaCl helper nexes, explicitly disable IRT loading.

ppapi/native_client/src/trusted/plugin/service_runtime.cc

 /*
  * Copyright (c) 2012 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.
  */
 
 #define NACL_LOG_MODULE_NAME "Plugin::ServiceRuntime"
 
 #include "native_client/src/trusted/plugin/service_runtime.h"
 
@@ skipping 694 matching lines @@
         ERROR_SEL_LDR_START_STATUS,
         NaClErrorString(static_cast<NaClErrorCode>(load_status)));
     return false;
   }
   return true;
 }
 
 bool ServiceRuntime::Start(nacl::DescWrapper* nacl_desc,
                            ErrorInfo* error_info,
                            const nacl::string& url,
+                           bool uses_irt,
                            bool uses_ppapi,
                            bool enable_ppapi_dev,
                            pp::CompletionCallback crash_cb) {
   PLUGIN_PRINTF(("ServiceRuntime::Start (nacl_desc=%p)\n",
                  reinterpret_cast<void*>(nacl_desc)));
 
   nacl::scoped_ptr<SelLdrLauncherChrome>
       tmp_subprocess(new SelLdrLauncherChrome());
   if (NULL == tmp_subprocess.get()) {
     PLUGIN_PRINTF(("ServiceRuntime::Start (subprocess create failed)\n"));
     error_info->SetReport(ERROR_SEL_LDR_CREATE_LAUNCHER,
                           "ServiceRuntime: failed to create sel_ldr launcher");
     return false;
   }
   bool started = tmp_subprocess->Start(plugin_->pp_instance(),
                                        url.c_str(),
+                                       uses_irt,
                                        uses_ppapi,
                                        enable_ppapi_dev);
   if (!started) {
     PLUGIN_PRINTF(("ServiceRuntime::Start (start failed)\n"));
     error_info->SetReport(ERROR_SEL_LDR_LAUNCH,
                           "ServiceRuntime: failed to start");
     return false;
   }
 
   subprocess_.reset(tmp_subprocess.release());
@@ skipping 102 matching lines @@
 
 nacl::string ServiceRuntime::GetCrashLogOutput() {
   if (NULL != subprocess_.get()) {
     return subprocess_->GetCrashLogOutput();
   } else {
     return "";
   }
 }
 
 }  // namespace plugin