Collect totals in placeOrder when no paymentMethod provided

Quote item values such as `base_original_price` are only populated during total
collection. Currently in `QuoteManagement::placeOrder` if `$paymentMethod` is
passed `Payment::importData` collects the quote totals to populate these values.

Payment methods like Auth.net DirectPost do pass a value for `$paymentMethod`
during order placement which causes order items to be converted with zero
values for the `original_price` attributes.

Fixes #16050

Author: pmclain

app/code/Magento/Quote/Model/QuoteManagement.php

@@ -349,6 +349,8 @@ public function placeOrder($cartId, PaymentInterface $paymentMethod = null)
 
             $data = $paymentMethod->getData();
             $quote->getPayment()->importData($data);
+        } else {
+            $quote->collectTotals();
         }
 
         if ($quote->getCheckoutMethod() === self::METHOD_GUEST) {

app/code/Magento/Quote/Test/Unit/Model/QuoteManagementTest.php

@@ -188,6 +188,7 @@ protected function setUp()
                 'setCustomerGroupId',
                 'assignCustomer',
                 'getPayment',
+                'collectTotals'
             ]);
 
         $this->quoteAddressFactory = $this->createPartialMock(
@@ -687,6 +688,7 @@ public function testPlaceOrderIfCustomerIsGuest()
         $service->expects($this->once())->method('submit')->willReturn($orderMock);
 
         $this->quoteMock->expects($this->atLeastOnce())->method('getId')->willReturn($cartId);
+        $this->quoteMock->expects($this->once())->method('collectTotals')->willReturnSelf();
 
         $orderMock->expects($this->atLeastOnce())->method('getId')->willReturn($orderId);
         $orderMock->expects($this->atLeastOnce())->method('getIncrementId')->willReturn($orderIncrementId);