BUG#AC-2242:Error:Cart Price rule forces Free Shipping to "No" even if "-- Please Select --" was saved

Author: RaghavendraTirumalasetti

app/code/Magento/OfflineShipping/etc/db_schema.xml

@@ -38,7 +38,7 @@
         </constraint>
     </table>
     <table name="salesrule" resource="default" comment="Salesrule">
-        <column xsi:type="smallint" name="simple_free_shipping" unsigned="true" nullable="false"
+        <column xsi:type="smallint" name="simple_free_shipping" unsigned="true" nullable="true"
                 identity="false" default="0" comment="Simple Free Shipping"/>
     </table>
     <table name="sales_order_item" resource="sales" comment="Sales Flat Order Item">

app/code/Magento/SalesRule/Controller/Adminhtml/Promo/Quote/Save.php

@@ -63,6 +63,9 @@ public function __construct(
     public function execute()
     {
         $data = $this->getRequest()->getPostValue();
+        if ($data['simple_free_shipping']==="") {
+            $data['simple_free_shipping']=null;
+        }
         if ($data) {
             try {
                 /** @var $model \Magento\SalesRule\Model\Rule */