The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2525f9688bbb6fd26ff12d38a7c4ee5f31404122

commit 2525f9688bbb6fd26ff12d38a7c4ee5f31404122
Author: rouslan <rouslan@chromium.org>
Date: Tue Aug 23 23:22:23 2016

Separate PaymentRequest initialization and display.

In order to better accommodate delays in querying payment apps, separate
initialization of PaymentRequest from displaying it. Thus a merchant
website can create a JavaScript PaymentRequest object on page load, but
call PaymentRequest.show() only when user clicks the [BUY] button on the
page. With this patch, Chrome begins to query the installed payment apps
before the user clicks the [BUY] button. This enables faster startup of
the PaymentRequest UI.

BUG= 638454 

Review-Url: https://codereview.chromium.org/2250793003
Cr-Commit-Position: refs/heads/master@{#413893}

[modify] https://crrev.com/2525f9688bbb6fd26ff12d38a7c4ee5f31404122/chrome/android/java/src/org/chromium/chrome/browser/payments/PaymentRequestFactory.java
[modify] https://crrev.com/2525f9688bbb6fd26ff12d38a7c4ee5f31404122/chrome/android/java/src/org/chromium/chrome/browser/payments/PaymentRequestImpl.java
[modify] https://crrev.com/2525f9688bbb6fd26ff12d38a7c4ee5f31404122/chrome/android/java/src/org/chromium/chrome/browser/payments/ui/PaymentRequestUI.java
[modify] https://crrev.com/2525f9688bbb6fd26ff12d38a7c4ee5f31404122/chrome/android/javatests/src/org/chromium/chrome/browser/payments/PaymentRequestMetricsTest.java
[modify] https://crrev.com/2525f9688bbb6fd26ff12d38a7c4ee5f31404122/third_party/WebKit/LayoutTests/payments/resources/payment-request-mock.js
[modify] https://crrev.com/2525f9688bbb6fd26ff12d38a7c4ee5f31404122/third_party/WebKit/Source/modules/payments/OnPaymentResponseTest.cpp
[modify] https://crrev.com/2525f9688bbb6fd26ff12d38a7c4ee5f31404122/third_party/WebKit/Source/modules/payments/PaymentRequest.cpp
[modify] https://crrev.com/2525f9688bbb6fd26ff12d38a7c4ee5f31404122/third_party/WebKit/Source/modules/payments/PaymentRequest.h
[modify] https://crrev.com/2525f9688bbb6fd26ff12d38a7c4ee5f31404122/third_party/WebKit/Source/modules/payments/PaymentRequestTest.cpp
[modify] https://crrev.com/2525f9688bbb6fd26ff12d38a7c4ee5f31404122/third_party/WebKit/public/platform/modules/payments/payment_request.mojom