Sync braintree config with customer's data.

This commit fixes the case when customer navigates back
to the shipping step and change address fields.

Author: vovayatsyuk

app/code/Magento/Braintree/view/frontend/web/js/view/payment/method-renderer/paypal.js

@@ -7,6 +7,7 @@
 define([
     'jquery',
     'underscore',
+    'mage/utils/wrapper',
     'Magento_Checkout/js/view/payment/default',
     'Magento_Braintree/js/view/payment/adapter',
     'Magento_Checkout/js/model/quote',
@@ -18,6 +19,7 @@ define([
 ], function (
     $,
     _,
+    wrapper,
     Component,
     Braintree,
     quote,
@@ -218,8 +220,9 @@ define([
 
         /**
          * Re-init PayPal Auth Flow
+         * @param {Function} callback Optional callback
          */
-        reInitPayPal: function () {
+        reInitPayPal: function (callback) {
             if (Braintree.checkout) {
                 Braintree.checkout.teardown(function () {
                     Braintree.checkout = null;
@@ -228,6 +231,18 @@ define([
 
             this.disableButton();
             this.clientConfig.paypal.amount = this.grandTotalAmount;
+            this.clientConfig.paypal.shippingAddressOverride = this.getShippingAddress();
+
+            if (callback) {
+                this.clientConfig.onReady = wrapper.wrap(
+                    this.clientConfig.onReady,
+                    function (original, checkout) {
+                        this.clientConfig.onReady = original;
+                        original(checkout);
+                        callback();
+                    }.bind(this)
+                );
+            }
 
             Braintree.setConfig(this.clientConfig);
             Braintree.setup();
@@ -404,15 +419,19 @@ define([
          * Triggers when customer click "Continue to PayPal" button
          */
         payWithPayPal: function () {
-            if (additionalValidators.validate()) {
+            this.reInitPayPal(function () {
+                if (!additionalValidators.validate()) {
+                    return;
+                }
+
                 try {
                     Braintree.checkout.paypal.initAuthFlow();
                 } catch (e) {
                     this.messageContainer.addErrorMessage({
                         message: $t('Payment ' + this.getTitle() + ' can\'t be initialized.')
                     });
                 }
-            }
+            }.bind(this));
         },
 
         /**