Make Script non-TraceWrapperBase and add a comment about ModuleScript tracing

third_party/WebKit/Source/core/dom/ModuleScript.cpp

 // Copyright 2017 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 "core/dom/ModuleScript.h"
 
 namespace blink {
 
 void ModuleScript::SetInstantiationError(v8::Isolate* isolate,
                                          v8::Local<v8::Value> error) {
   DCHECK_EQ(instantiation_state_, ModuleInstantiationState::kUninstantiated);
   instantiation_state_ = ModuleInstantiationState::kErrored;
 
   DCHECK(!error.IsEmpty());
   instantiation_error_.Set(isolate, error);
 }
 
 void ModuleScript::SetInstantiationSuccess() {
   DCHECK_EQ(instantiation_state_, ModuleInstantiationState::kUninstantiated);
   instantiation_state_ = ModuleInstantiationState::kInstantiated;
 }
 
 DEFINE_TRACE(ModuleScript) {
   Script::Trace(visitor);
 }
 DEFINE_TRACE_WRAPPERS(ModuleScript) {
-  Script::TraceWrappers(visitor);
   visitor->TraceWrappers(instantiation_error_);
 }
 
 bool ModuleScript::IsEmpty() const {
   return false;
 }
 
 bool ModuleScript::CheckMIMETypeBeforeRunScript(Document* context_document,
                                                 const SecurityOrigin*) const {
   // We don't check MIME type here because we check the MIME type in
   // ModuleScriptLoader::WasModuleLoadSuccessful().
   return true;
 }
 
 void ModuleScript::RunScript(LocalFrame* frame, const SecurityOrigin*) const {
   // TODO(hiroshige): Implement this once Modulator::ExecuteModule() is landed.
   NOTREACHED();
 }
 
 String ModuleScript::InlineSourceTextForCSP() const {
   // Currently we don't support inline module scripts.
   // TODO(hiroshige): Implement this.
   NOTREACHED();
   return String();
 }
 
 }  // namespace blink