[Payments] Normalize billing address before sending to the merchant.

chrome/android/java/src/org/chromium/chrome/browser/payments/PaymentInstrument.java

 // 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.
 
 package org.chromium.chrome.browser.payments;
 
+import org.json.JSONObject;
+
 import org.chromium.chrome.browser.payments.ui.PaymentOption;
 import org.chromium.payments.mojom.PaymentItem;
 
-import org.json.JSONObject;
-
 import java.util.List;
 
 /**
  * The base class for a single payment instrument, e.g., a credit card.
  */
 public abstract class PaymentInstrument extends PaymentOption {
     /**
      * The interface for the requester of instrument details.
      */
     public interface DetailsCallback {
         /**
+         * Called when loading the instrument details to tell the Payment Request UI to show a

[please use gerrit instead, 2016/10/18 17:30:31]

s/when loading the instrument details/by the credit card payment instrument when
CVC has been unmasked, but billing address has not been normalized yet/

[sebsg, 2016/10/18 22:44:31]

This is very specific. I left it more general so it could be used by other
PaymentInstruments while they do some background tasks. You know more about all
of that though so I'll defer to your take on this.

+         * loading UI.
+         */
+        void loadingInstrumentDetails();
+
+        /**
          * Called after retrieving instrument details.
          *
          * @param methodName         Method name. For example, "visa".
          * @param stringifiedDetails JSON-serialized object. For example, {"card": "123"}.
          */
         void onInstrumentDetailsReady(String methodName, String stringifiedDetails);
 
         /**
          * Called if unable to retrieve instrument details.
          */
@@ skipping 25 matching lines @@
      */
     public abstract void getDetails(String merchantName, String origin, PaymentItem total,
             List<PaymentItem> cart, JSONObject details, DetailsCallback callback);
 
     /**
      * Cleans up any resources held by the payment instrument. For example, closes server
      * connections.
      */
     public abstract void dismiss();
 }