Mojo: NULL -> nullptr in mojo/public/cpp outside of bindings.

mojo/public/cpp/application/lib/weak_service_provider.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 "mojo/public/cpp/application/lib/weak_service_provider.h"
 
 #include "mojo/public/cpp/application/service_provider_impl.h"
 #include "mojo/public/interfaces/application/service_provider.mojom.h"
 
 namespace mojo {
 namespace internal {
 
 WeakServiceProvider::WeakServiceProvider(ServiceProviderImpl* creator,
                                          ServiceProvider* service_provider)
       : creator_(creator),
         service_provider_(service_provider) {}
 
 WeakServiceProvider::~WeakServiceProvider() {
   if (creator_)
     creator_->ClearRemote();
 }
 
 void WeakServiceProvider::Clear() {
-  creator_ = NULL;
-  service_provider_ = NULL;
+  creator_ = nullptr;
+  service_provider_ = nullptr;
 }
 
 void WeakServiceProvider::ConnectToService(
     const String& service_name,
     ScopedMessagePipeHandle client_handle) {
   if (service_provider_)
     service_provider_->ConnectToService(service_name, client_handle.Pass());
 }
 
 }  // namespace internal
 }  // namespace mojo