MAGETWO-57862: [Backport] - Price in cart does not update correctly when price is changed in admin. - for 2.0

Author: OlgaVasyltsun

app/code/Magento/Checkout/Model/TotalsInformationManagement.php

@@ -56,6 +56,10 @@ public function calculate(
                 $addressInformation->getShippingCarrierCode() . '_' . $addressInformation->getShippingMethodCode()
             );
         }
+
+        if ($quote->getShippingAddress()->dataHasChangedFor('shipping_method')) {
+            $quote->setTotalsCollectedFlag(false);
+        }
         $quote->collectTotals();
 
         return $this->cartTotalRepository->get($cartId);