[Payments] Add a Pay button in the Order summary screen

components/payments/content/payment_request.cc

 // Copyright 2016 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 "components/payments/content/payment_request.h"
 
 #include <algorithm>
 #include <unordered_map>
 #include <utility>
 
@@ skipping 94 matching lines @@
   client_.reset();
   binding_.Close();
   delegate_->CloseDialog();
   manager_->DestroyRequest(this);
 }
 
 void PaymentRequest::Pay() {
   DCHECK(is_ready_to_pay_);
 
   // TODO(mathp): Return the PaymentResponse to the |client_|.
-  UserCancelled();
+  OnConnectionTerminated();
 }
 
 void PaymentRequest::AddObserver(Observer* observer) {
   CHECK(observer);
   observers_.AddObserver(observer);
 }
 
 void PaymentRequest::RemoveObserver(Observer* observer) {
   observers_.RemoveObserver(observer);
 }
@@ skipping 198 matching lines @@
            ->GetInfo(autofill::AutofillType(autofill::PHONE_HOME_WHOLE_NUMBER),
                      app_locale)
            .empty())) {
     return false;
   }
 
   return true;
 }
 
 }  // namespace payments