MAGETWO-49446: Unable to place order with PayPal Express Checkout using shortcut flow with secure URLs

 - Added PayPal Express to list of secure urls

Author: YevSent

app/code/Magento/Paypal/etc/frontend/di.xml

@@ -48,6 +48,7 @@
                 <item name="paypal_payflowbml" xsi:type="string">/paypal/payflowbml/</item>
                 <item name="paypal_payflowexpress" xsi:type="string">/paypal/payflowexpress/</item>
                 <item name="paypal_transparent" xsi:type="string">/paypal/transparent/</item>
+                <item name="paypal_express" xsi:type="string">/paypal/express/</item>
             </argument>
         </arguments>
     </type>