[Refactor] parse: use utils.combine more

Author: ljharb

lib/parse.js

@@ -155,7 +155,7 @@ var parseObject = function (chain, val, options, valuesParsed) {
         if (root === '[]' && options.parseArrays) {
             obj = options.allowEmptyArrays && (leaf === '' || (options.strictNullHandling && leaf === null))
                 ? []
-                : [].concat(leaf);
+                : utils.combine([], leaf);
         } else {
             obj = options.plainObjects ? { __proto__: null } : {};
             var cleanRoot = root.charAt(0) === '[' && root.charAt(root.length - 1) === ']' ? root.slice(1, -1) : root;