Mojo: NULL -> nullptr in mojo/public/cpp/bindings and also for the bindings generator.

mojo/public/tools/bindings/generators/cpp_templates/interface_definition.tmpl

 {%- import "interface_macros.tmpl" as interface_macros %}
 {%- set class_name = interface.name %}
 {%- set proxy_name = interface.name ~ "Proxy" %}
 {%- set namespace_as_string = "%s"|format(namespace|replace(".","::")) %}
 
 {%- macro alloc_params(parameters) %}
 {%-   for param in parameters %}
 {%-     if param.kind|is_object_kind  %}
 {{param.kind|cpp_result_type}} p{{loop.index}};
 Deserialize_(params->{{param.name}}.ptr, &p{{loop.index}});
@@ skipping 184 matching lines @@
     {{interface_macros.declare_params("in_", method.response_parameters)}}) const {
   {{compute_payload_size(params_name, method.response_parameters)}}
   mojo::internal::ResponseMessageBuilder builder(
       {{message_name}}, payload_size, request_id_);
   {{build_message(params_name, method.response_parameters, params_description)}}
   bool ok MOJO_ALLOW_UNUSED = responder_->Accept(&message);
   // TODO(darin): !ok returned here indicates a malformed message, and that may
   // be good reason to close the connection. However, we don't have a way to do
   // that from here. We should add a way.
   delete responder_;
-  responder_ = NULL;
+  responder_ = nullptr;
 }
 {%-   endif -%}
 {%- endfor %}
 
 {{class_name}}Stub::{{class_name}}Stub()
-    : sink_(NULL) {
+    : sink_(nullptr) {
 }
 
 {#--- Stub definition #}
 
 bool {{class_name}}Stub::Accept(mojo::Message* message) {
 {%- if interface.methods %}
   switch (message->header()->name) {
 {%-   for method in interface.methods %}
     case internal::k{{class_name}}_{{method.name}}_Name: {
 {%-     if method.response_parameters == None %}
@@ skipping 103 matching lines @@
       }
       break;
     }
 {%-   endfor %}
   }
 {%- endif %}
 
   return sink_->Accept(message);
 }
 {%- endif -%}