bindings: Make the sequence conversion code more compliant 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 0cece6fb5df98bcf4bd6fa4530b3a80a665c04ee..f837319cd11e38a15a836abe1db35fe4baacd0e6 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& exception_state) {
+    return ScriptValue(ScriptState::Current(isolate), value);
+  }
+};
+
 }  // namespace blink
 
 #endif  // ScriptValue_h