Reland of NaCl cleanup: Split out irt_interfaces.cc from irt_ppapi.cc

ppapi/nacl_irt/irt_start.cc

 // Copyright 2014 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.
 
 #include "build/build_config.h"
 
 // We need nacl_irt_start injection in SFI mode. Non-SFI has a different
 // start up procedure so we just exclude it.
 #if defined(OS_NACL_SFI)
 
 #include "base/at_exit.h"
 #include "native_client/src/public/chrome_main.h"
 #include "native_client/src/public/irt_core.h"
-#include "ppapi/nacl_irt/irt_ppapi.h"
+#include "ppapi/nacl_irt/irt_interfaces.h"
 #include "ppapi/nacl_irt/plugin_startup.h"
 
 void nacl_irt_start(uint32_t* info) {
   nacl_irt_init(info);
 
   // Though it isn't referenced here, we must instantiate an AtExitManager.
   base::AtExitManager exit_manager;
 
   // In SFI mode, the FDs of IPC channels are NACL_CHROME_DESC_BASE and its
   // successor, which is set in nacl_listener.cc.
   ppapi::SetIPCFileDescriptors(
       NACL_CHROME_DESC_BASE,
       NACL_CHROME_DESC_BASE + 1,
       NACL_CHROME_DESC_BASE + 2);
   ppapi::StartUpPlugin();
 
   nacl_irt_enter_user_code(info, chrome_irt_query);
 }
 
 #endif  // defined(OS_NACL_SFI)