PaymentHandler: PaymentRequestEvent.total should be |object| type.

third_party/WebKit/Source/modules/payments/PaymentRequestEvent.idl

 // Copyright 2016 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.
 
 // https://w3c.github.io/payment-handler/#the-paymentrequestevent
 
 [
     RuntimeEnabled=PaymentApp,
     Constructor(DOMString type, PaymentRequestEventInit eventInitDict),
     Exposed=ServiceWorker
 ] interface PaymentRequestEvent : ExtendableEvent {
     readonly attribute USVString topLevelOrigin;
     readonly attribute USVString paymentRequestOrigin;
     readonly attribute DOMString paymentRequestId;
     readonly attribute FrozenArray<PaymentMethodData> methodData;
-    readonly attribute PaymentItem total;
+    [CallWith=ScriptState] readonly attribute object total;
     readonly attribute FrozenArray<PaymentDetailsModifier> modifiers;
     readonly attribute DOMString instrumentKey;
 
     [CallWith=ScriptState] Promise<WindowClient> openWindow(USVString url);
     [CallWith=ScriptState, RaisesException] void respondWith(Promise<PaymentResponse> response);
 };