MAGETWO-31191: Page JS dependencies optimization

 - Add var definition to validation.js

Author: Mykhailo Miroshnikov

lib/web/mage/backend/validation.js

@@ -233,7 +233,9 @@
         'validate-downloadable-file': [
             function (v, element) {
                 var elmParent = $(element).parent(),
-                    linkType = elmParent.find('input[value="file"]');
+                    linkType = elmParent.find('input[value="file"]'),
+                    newFileContainer;
+
                 if (linkType.is(':checked') && (v === '' || v === '[]')) {
                     newFileContainer = elmParent.find('.new-file');
                     if (!alertAlreadyDisplayed && (newFileContainer.empty() || newFileContainer.is(':visible'))) {