[ES6 modules] Fix context leak. ModuleScript should use TraceWrapperV8Reference to hold onto v8::Mo…

third_party/WebKit/Source/bindings/core/v8/ScriptModule.h

 // 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.
 
 #ifndef ScriptModule_h
 #define ScriptModule_h
 
 #include "core/CoreExport.h"
 #include "platform/bindings/ScriptState.h"
 #include "platform/bindings/SharedPersistent.h"
@@ skipping 59 matching lines @@
     return *left == *right;
   }
 
   bool operator!=(const blink::ScriptModule& other) const {
     return !(*this == other);
   }
 
   bool IsNull() const { return !module_ || module_->IsEmpty(); }
 
  private:
+  // ModuleScript instances store their record as
+  // TraceWrapperV8Reference<v8::Module>, and reconstructs ScriptModule from it.
+  friend class ModuleScript;
+
   ScriptModule(v8::Isolate*, v8::Local<v8::Module>);
 
+  v8::Local<v8::Module> NewLocal(v8::Isolate* isolate) {
+    return module_->NewLocal(isolate);
+  }
+
   static v8::MaybeLocal<v8::Module> ResolveModuleCallback(
       v8::Local<v8::Context>,
       v8::Local<v8::String> specifier,
       v8::Local<v8::Module> referrer);
 
   RefPtr<SharedPersistent<v8::Module>> module_;
   unsigned identity_hash_ = 0;
 
   friend struct ScriptModuleHash;
 };
@@ skipping 23 matching lines @@
   using Hash = blink::ScriptModuleHash;
 };
 
 template <>
 struct HashTraits<blink::ScriptModule>
     : public SimpleClassHashTraits<blink::ScriptModule> {};
 
 }  // namespace WTF
 
 #endif  // ScriptModule_h