Disable dropdown in JavaScript and CSS Settings in developer configuration

Author: ananth-iyer

app/code/Magento/Backend/etc/adminhtml/system.xml

@@ -169,27 +169,27 @@
             </group>
             <group id="js" translate="label" type="text" sortOrder="100" showInDefault="1" showInWebsite="1" showInStore="1">
                 <label>JavaScript Settings</label>
-                <field id="merge_files" translate="label" type="select" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1">
+                <field id="merge_files" translate="label" type="select" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1" canRestore="1">
                     <label>Merge JavaScript Files</label>
                     <source_model>Magento\Config\Model\Config\Source\Yesno</source_model>
                 </field>
-                <field id="enable_js_bundling" translate="label" type="select" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1">
+                <field id="enable_js_bundling" translate="label" type="select" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1" canRestore="1">
                     <label>Enable JavaScript Bundling</label>
                     <source_model>Magento\Config\Model\Config\Source\Yesno</source_model>
                 </field>
-                <field id="minify_files" translate="label comment" type="select" sortOrder="20" showInDefault="1" showInWebsite="1" showInStore="1">
+                <field id="minify_files" translate="label comment" type="select" sortOrder="20" showInDefault="1" showInWebsite="1" showInStore="1" canRestore="1">
                     <label>Minify JavaScript Files</label>
                     <source_model>Magento\Config\Model\Config\Source\Yesno</source_model>
                     <comment>Minification is not applied in developer mode.</comment>
                 </field>
             </group>
             <group id="css" translate="label" type="text" sortOrder="110" showInDefault="1" showInWebsite="1" showInStore="1">
                 <label>CSS Settings</label>
-                <field id="merge_css_files" translate="label" type="select" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1">
+                <field id="merge_css_files" translate="label" type="select" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="1" canRestore="1">
                     <label>Merge CSS Files</label>
                     <source_model>Magento\Config\Model\Config\Source\Yesno</source_model>
                 </field>
-                <field id="minify_files" translate="label comment" type="select" sortOrder="20" showInDefault="1" showInWebsite="1" showInStore="1">
+                <field id="minify_files" translate="label comment" type="select" sortOrder="20" showInDefault="1" showInWebsite="1" showInStore="1" canRestore="1">
                     <label>Minify CSS Files</label>
                     <source_model>Magento\Config\Model\Config\Source\Yesno</source_model>
                     <comment>Minification is not applied in developer mode.</comment>