CallbackPromiseAdapter types should be more compatible with WebCallbacks (3/3).

Source/modules/app_banner/AppBannerPromptResult.cpp

 // Copyright 2015 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.
 
 #include "config.h"
 #include "modules/app_banner/AppBannerPromptResult.h"
 
 #include "public/platform/modules/app_banner/WebAppBannerPromptResult.h"
 
 namespace blink {
 
 // static
-AppBannerPromptResult* AppBannerPromptResult::take(ScriptPromiseResolver* resolver, PassOwnPtr<WebAppBannerPromptResult> webInstance)
+AppBannerPromptResult* AppBannerPromptResult::take(ScriptPromiseResolver* resolver, const WebAppBannerPromptResult& webInstance)
 {
-    return webInstance ? AppBannerPromptResult::create(webInstance->platform, webInstance->outcome) : nullptr;
+    return AppBannerPromptResult::create(webInstance.platform, webInstance.outcome);
 }
 
 AppBannerPromptResult::~AppBannerPromptResult()
 {
 }
 
 String AppBannerPromptResult::outcome() const
 {
     switch (m_outcome) {
     case WebAppBannerPromptResult::Outcome::Accepted:
         return "accepted";
 
     case WebAppBannerPromptResult::Outcome::Dismissed:
         return "dismissed";
     }
 
     ASSERT_NOT_REACHED();
     return "";
 }
 
 AppBannerPromptResult::AppBannerPromptResult(const AtomicString& platform, WebAppBannerPromptResult::Outcome outcome)
     : m_platform(platform)
     , m_outcome(outcome)
 {
 }
 
 } // namespace blink