payments: Avoid dynamic allocation of HeapVector

Bug: 1154667
Change-Id: I16e5f4d099ce9a3bbabe7c6e7888fd541038d151
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2569667
Auto-Submit: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#833055}

third_party/blink/renderer/modules/payments/payment_request_event.cc

@@ -359,8 +359,7 @@ void PaymentRequestEvent::OnChangePaymentRequestDetailsResponse(
                                  "PaymentDetailsModifier");
 
   if (response->modifiers) {
-    auto* modifiers =
-        MakeGarbageCollected<HeapVector<Member<PaymentDetailsModifier>>>();
+    HeapVector<Member<PaymentDetailsModifier>> modifiers;
     for (const auto& response_modifier : *response->modifiers) {
       if (!response_modifier)
         continue;
@@ -390,15 +389,14 @@ void PaymentRequestEvent::OnChangePaymentRequestDetailsResponse(
           return;
         }
         mod->setData(ScriptValue(script_state->GetIsolate(), parsed_value));
-        modifiers->emplace_back(mod);
+        modifiers.emplace_back(mod);
       }
     }
-    dictionary->setModifiers(*modifiers);
+    dictionary->setModifiers(modifiers);
   }
 
   if (response->shipping_options) {
-    auto* shipping_options =
-        MakeGarbageCollected<HeapVector<Member<PaymentShippingOption>>>();
+    HeapVector<Member<PaymentShippingOption>> shipping_options;
     for (const auto& response_shipping_option : *response->shipping_options) {
       if (!response_shipping_option)
         continue;
@@ -411,9 +409,9 @@ void PaymentRequestEvent::OnChangePaymentRequestDetailsResponse(
       shipping_option->setId(response_shipping_option->id);
       shipping_option->setLabel(response_shipping_option->label);
       shipping_option->setSelected(response_shipping_option->selected);
-      shipping_options->emplace_back(shipping_option);
+      shipping_options.emplace_back(shipping_option);
     }
-    dictionary->setShippingOptions(*shipping_options);
+    dictionary->setShippingOptions(shipping_options);
   }
 
   if (response->stringified_payment_method_errors &&