Remove breaking change for PWA

Some PWA integrations can still use the session to retrieve the order
but in the next major release only the orderId request parameter can be
used to retrieve the order object

Model/AdyenThreeDS2Process.php

@@ -84,11 +84,14 @@ class AdyenThreeDS2Process implements AdyenThreeDS2ProcessInterface
         }
 
         if (empty($payload['orderId'])) {
-            throw new \Magento\Framework\Exception\LocalizedException(__('3D secure 2.0 failed because of a missing order id'));
-        }
-
+            $order = $this->getOrder();
+            // In the next major release remove support for retrieving order from session and throw exception instead
+            //throw new \Magento\Framework\Exception\LocalizedException(__('3D secure 2.0 failed because of a missing order id'));
+        } else {
             // Create order by order id
             $order = $this->orderFactory->create()->load($payload['orderId']);
+        }
+
         $payment = $order->getPayment();
 
         // Init payments/details request
@@ -157,4 +160,18 @@ class AdyenThreeDS2Process implements AdyenThreeDS2ProcessInterface
         $response['result'] = $result['resultCode'];
         return json_encode($response);
     }
+
+    /**
+     * Get order object
+     *
+     * @return \Magento\Sales\Model\Order
+     * @deprecated Will be removed in 7.0.0
+     */
+    protected function getOrder()
+    {
+        $incrementId = $this->checkoutSession->getLastRealOrderId();
+        $order = $this->orderFactory->create()->loadByIncrementId($incrementId);
+
+        return $order;
+    }
 }