bindings: Make the sequence conversion code more complaint with WebIDL.

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

Index: third_party/WebKit/Source/bindings/core/v8/ScriptValue.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/ScriptValue.h b/third_party/WebKit/Source/bindings/core/v8/ScriptValue.h
index 98a37d7adf6a74441975407e35fed7d6c0ed9438..f282b6fc537b04263a2cc3541f8f3ed65b9b1687 100644
--- a/third_party/WebKit/Source/bindings/core/v8/ScriptValue.h
+++ b/third_party/WebKit/Source/bindings/core/v8/ScriptValue.h
@@ -174,6 +174,16 @@ class CORE_EXPORT ScriptValue final {
   RefPtr<SharedPersistent<v8::Value>> value_;
 };
 
+template <>
+struct NativeValueTraits<ScriptValue>
+    : public NativeValueTraitsBase<ScriptValue> {
+  static inline ScriptValue NativeValue(v8::Isolate* isolate,
+                                        v8::Local<v8::Value> value,
+                                        ExceptionState&) {
+    return ScriptValue(ScriptState::Current(isolate), value);
+  }
+};
+
 }  // namespace blink
 
 #endif  // ScriptValue_h