[Payment Request] Change the lifetime management of PaymentRequestImpl

components/payments/payment_request_delegate.h

+// 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.
+
+#ifndef COMPONENTS_PAYMENTS_PAYMENT_REQUEST_DELEGATE_H_
+#define COMPONENTS_PAYMENTS_PAYMENT_REQUEST_DELEGATE_H_
+
+namespace payments {
+
+class PaymentRequest;
+
+class PaymentRequestDelegate {
+ public:
+  virtual ~PaymentRequestDelegate() {}
+
+  // Shows the Payment Request dialog for the given |request|.
+  virtual void ShowPaymentRequestDialog(PaymentRequest* request) = 0;
+};
+
+}  // namespace payments
+
+#endif  // COMPONENTS_PAYMENTS_PAYMENT_REQUEST_DELEGATE_H_