[Payments] Present web payment app instead of instruments to user

content/browser/payments/payment_app_info_fetcher.cc

 // Copyright 2017 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 "content/browser/payments/payment_app_info_fetcher.h"
 
 #include "base/base64.h"
 #include "base/bind_helpers.h"
 #include "content/browser/frame_host/render_frame_host_impl.h"
 #include "content/browser/service_worker/service_worker_context_wrapper.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/manifest_icon_downloader.h"
 #include "content/public/browser/manifest_icon_selector.h"
 #include "ui/gfx/image/image.h"
 
 namespace content {
 
 namespace {
 
 // TODO(gogerald): Choose appropriate icon size dynamically on different
 // platforms.
-const int kPaymentAppIdealIconSize = 64;
+// Here we choose a large ideal icon size to be big enough for all platforms.
+// Note that we only scale down for this icon size but not scale up.
+const int kPaymentAppIdealIconSize = 0xFFFF;

[please use gerrit instead, 2017/07/05 13:14:22]

Why jump from 64 to 65535?

[gogerald1, 2017/07/05 19:49:39]

As I mentioned in the above comments. 64 pixels is small which will cause the
image be scaled down. So I am choosing a large enough value for all platforms.

 const int kPaymentAppMinimumIconSize = 0;
 
 }  // namespace
 
 PaymentAppInfoFetcher::PaymentAppInfoFetcher()
     : context_process_id_(-1), context_frame_id_(-1) {}
 PaymentAppInfoFetcher::~PaymentAppInfoFetcher() {}
 
 void PaymentAppInfoFetcher::Start(
     const GURL& context_url,
@@ skipping 114 matching lines @@
 void PaymentAppInfoFetcher::PostPaymentAppInfoFetchResultToIOThread() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       base::BindOnce(std::move(callback_), fetched_payment_app_name_,
                      fetched_payment_app_icon_));
 }
 
 }  // namespace content