Reland: Test dismissing CVC prompt for PaymentRequest

chrome/android/java/src/org/chromium/chrome/browser/payments/ui/PaymentRequestUI.java

Index: chrome/android/java/src/org/chromium/chrome/browser/payments/ui/PaymentRequestUI.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/payments/ui/PaymentRequestUI.java b/chrome/android/java/src/org/chromium/chrome/browser/payments/ui/PaymentRequestUI.java
index e03ce067026049c877e8af3a9d5547ab03c63c12..998258846b46168b4caa8cd7c961949869efbe1f 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/payments/ui/PaymentRequestUI.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/payments/ui/PaymentRequestUI.java
@@ -130,6 +130,11 @@ public class PaymentRequestUI implements DialogInterface.OnDismissListener, View
         void onPaymentRequestReadyToPay(PaymentRequestUI ui);
 
         /**
+         * Called when the result UI is showing.
+         */
+        void onPaymentRequestResultReady(PaymentRequestUI ui);
+
+        /**
          * Called when the UI is gone.
          */
         void onPaymentRequestDismiss();
@@ -352,6 +357,7 @@ public class PaymentRequestUI implements DialogInterface.OnDismissListener, View
                 if (callback != null) callback.run();
             }
         });
+        if (mObserverForTest != null) mObserverForTest.onPaymentRequestResultReady(this);
     }
 
     /**