MC-6279: Generic checkout skeleton flow

-- fix a performance degradation

Author: fascinosum

app/code/Magento/Config/etc/adminhtml/di.xml

@@ -6,7 +6,6 @@
  */
 -->
 <config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
-    <preference for="Magento\Config\Model\Config\Structure\SearchInterface" type="Magento\Config\Model\Config\Structure" />
     <preference for="Magento\Config\Model\Config\Backend\File\RequestData\RequestDataInterface" type="Magento\Config\Model\Config\Backend\File\RequestData" />
     <preference for="Magento\Config\Model\Config\Structure\ElementVisibilityInterface" type="Magento\Config\Model\Config\Structure\ElementVisibilityComposite" />
     <type name="Magento\Config\Model\Config\Structure\Element\Iterator\Tab" shared="false" />

app/code/Magento/Variable/etc/di.xml

@@ -42,6 +42,7 @@
                     <item name="general/store_information/merchant_vat_number" xsi:type="string">1</item>
                 </item>
             </argument>
+            <argument name="configStructure" xsi:type="object">Magento\Config\Model\Config\Structure\Proxy</argument>
         </arguments>
     </type>
-</config>
+</config>