Remove overArg.

.internal/nativeKeys.js

@@ -1,6 +1,14 @@
-import overArg from './.internal/overArg.js';
-
-/* Built-in method references for those with the same name as other `lodash` methods. */
-const nativeKeys = overArg(Object.keys, Object);
+/**
+ * This function is a thin wrapper around
+ * [`Object.keys`](http://ecma-international.org/ecma-262/7.0/#sec-object.keys)
+ * which ensures non-object values are coerced to objects beforehand.
+ *
+ * @private
+ * @param {Object} object The object to query.
+ * @returns {Array} Returns the array of property names.
+ */
+function nativeKeys(object) {
+  return Object.keys(Object(object));
+}
 
 export default nativeKeys;

.internal/overArg.js

@@ -1,13 +0,0 @@
-/**
- * Creates a unary function that invokes `func` with its argument transformed.
- *
- * @private
- * @param {Function} func The function to wrap.
- * @param {Function} transform The argument transform.
- * @returns {Function} Returns the new function.
- */
-function overArg(func, transform) {
-  return arg => func(transform(arg));
-}
-
-export default overArg;