replace NULL->nullptr in src/remoting.

remoting/client/plugin/pepper_entrypoints.cc

 // Copyright (c) 2011 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 "remoting/client/plugin/pepper_entrypoints.h"
 
 #include "base/message_loop/message_loop.h"
 #include "ppapi/c/pp_errors.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_module.h"
@@ skipping 25 matching lines @@
   // Register a global log handler, but only in Debug builds.
   ChromotingInstance::RegisterLogMessageHandler();
 #endif
 
   pp::InternalSetModuleSingleton(module);
   return PP_OK;
 }
 
 void PPP_ShutdownModule() {
   delete pp::Module::Get();
-  pp::InternalSetModuleSingleton(NULL);
+  pp::InternalSetModuleSingleton(nullptr);
 }
 
 const void* PPP_GetInterface(const char* interface_name) {
   if (!pp::Module::Get())
-    return NULL;
+    return nullptr;
   return pp::Module::Get()->GetPluginInterface(interface_name);
 }
 
 const void* PPP_GetBrowserInterface(const char* interface_name) {
   if (!pp::Module::Get())
-    return NULL;
+    return nullptr;
   return pp::Module::Get()->GetBrowserInterface(interface_name);
 }
 
 }  // namespace remoting