Convert app banners to use Mojo.

third_party/WebKit/Source/modules/app_banner/AppBannerCallbacks.h

-// 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.
-
-#ifndef AppBannerCallbacks_h
-#define AppBannerCallbacks_h
-
-#include "modules/app_banner/BeforeInstallPromptEvent.h"
-#include "public/platform/modules/app_banner/WebAppBannerClient.h"
-
-namespace blink {
-
-class AppBannerCallbacks : public WebAppBannerCallbacks {
-  // FIXME(tasak): when making public/platform classes to use PartitionAlloc,
-  // the following macro should be moved to WebCallbacks defined in
-  // public/platformWebCallbacks.h.
-  USING_FAST_MALLOC(AppBannerCallbacks);
-
- public:
-  explicit AppBannerCallbacks(UserChoiceProperty*);
-  ~AppBannerCallbacks() override = default;
-
-  // WebAppBannerCallbacks overrides.
-  void onSuccess(const WebAppBannerPromptResult&) override;
-
- private:
-  Persistent<UserChoiceProperty> m_userChoice;
-};
-
-}  // namespace blink
-
-#endif  // AppBannerCallbacks_h