When launching PNaCl helper nexes, explicitly disable IRT loading.

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

 /* -*- c++ -*- */
 /*
  * 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.
  */
 
 // A class containing information regarding a socket connection to a
 // service runtime instance.
 
@@ skipping 220 matching lines @@
   // The destructor terminates the sel_ldr process.
   ~ServiceRuntime();
 
   // Spawn a sel_ldr instance and establish an SrpcClient to it.  The nexe
   // to be started is passed through |nacl_file_desc|.  On success, returns
   // true.  On failure, returns false and |error_string| is set to something
   // describing the error.
   bool Start(nacl::DescWrapper* nacl_file_desc,
              ErrorInfo* error_info,
              const nacl::string& url,
+             bool uses_irt,
              bool uses_ppapi,
              bool enable_ppapi_dev,
              pp::CompletionCallback crash_cb);
 
   // Starts the application channel to the nexe.
   SrpcClient* SetupAppChannel();
 
   bool Log(int severity, const nacl::string& msg);
   Plugin* plugin() const { return plugin_; }
   void Shutdown();
@@ skipping 25 matching lines @@
 
   PluginReverseInterface* rev_interface_;
 
   NaClMutex mu_;
   int exit_status_;
 };
 
 }  // namespace plugin
 
 #endif  // NATIVE_CLIENT_SRC_TRUSTED_PLUGIN_SERVICE_RUNTIME_H_