MAGETWO-66656: Fix retrieval of old value in config import

Author: shiftedreality

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

@@ -86,19 +86,6 @@
             <argument name="serializer" xsi:type="object">Magento\Framework\Serialize\Serializer\Serialize</argument>
         </arguments>
     </type>
-    <virtualType name="systemSnapshot" type="Magento\Config\App\Config\Type\System">
-        <arguments>
-            <argument name="source" xsi:type="object">systemConfigSnapshotSourceAggregated</argument>
-            <argument name="configType" xsi:type="string">system_snapshot</argument>
-        </arguments>
-    </virtualType>
-    <virtualType name="configSnapshot" type="Magento\Framework\App\Config">
-        <arguments>
-            <argument name="types" xsi:type="array">
-                <item name="system" xsi:type="object">systemSnapshot</item>
-            </argument>
-        </arguments>
-    </virtualType>
     <virtualType name="modulesDataProviderProxy" type="Magento\Framework\App\Config\InitialConfigSource\Proxy">
         <arguments>
             <argument name="instanceName" xsi:type="string">modulesDataProvider</argument>
@@ -137,24 +124,6 @@
         </arguments>
     </virtualType>
     <virtualType name="systemConfigSourceAggregated" type="Magento\Framework\App\Config\ConfigSourceAggregated">
-        <arguments>
-            <argument name="sources" xsi:type="array">
-                <item name="modular" xsi:type="array">
-                    <item name="source" xsi:type="object">Magento\Config\App\Config\Source\ModularConfigSource</item>
-                    <item name="sortOrder" xsi:type="string">10</item>
-                </item>
-                <item name="dynamic" xsi:type="array">
-                    <item name="source" xsi:type="object">Magento\Config\App\Config\Source\RuntimeConfigSource</item>
-                    <item name="sortOrder" xsi:type="string">100</item>
-                </item>
-                <item name="initial" xsi:type="array">
-                    <item name="source" xsi:type="object">systemConfigInitialDataProvider</item>
-                    <item name="sortOrder" xsi:type="string">1000</item>
-                </item>
-            </argument>
-        </arguments>
-    </virtualType>
-    <virtualType name="systemConfigSnapshotSourceAggregated" type="Magento\Framework\App\Config\ConfigSourceAggregated">
         <arguments>
             <argument name="sources" xsi:type="array">
                 <item name="modular" xsi:type="array">
@@ -279,9 +248,4 @@
             </argument>
         </arguments>
     </type>
-    <type name="Magento\Framework\App\Config\Value">
-        <arguments>
-            <argument name="config" xsi:type="object">configSnapshot</argument>
-        </arguments>
-    </type>
 </config>