[Payments] Use the correct index when checking addresses

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 923186672f027930f7800d42ee30d443c0e54a50..56ae6daa373d0551fd51eb12c6f91b6ac6c88274 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
@@ -194,6 +194,11 @@ public class PaymentRequestUI implements DialogInterface.OnDismissListener, View
         void onPaymentRequestReadyToPay(PaymentRequestUI ui);
 
         /**
+         * Called when the UI has been updated to reflect checking a selected option.
+         */
+        void onPaymentRequestSelectionChecked(PaymentRequestUI ui);
+
+        /**
          * Called when edit dialog is showing.
          */
         void onPaymentRequestReadyToEdit();
@@ -329,6 +334,7 @@ public class PaymentRequestUI implements DialogInterface.OnDismissListener, View
                     expand(null);
                 }
                 updatePayButtonEnabled();
+                notifySelectionChecked();
             }
         };
 
@@ -1168,4 +1174,10 @@ public class PaymentRequestUI implements DialogInterface.OnDismissListener, View
             sObserverForTest.onPaymentRequestReadyToClose(this);
         }
     }
+
+    private void notifySelectionChecked() {
+        if (sObserverForTest != null) {
+            sObserverForTest.onPaymentRequestSelectionChecked(this);
+        }
+    }
 }