Remove nativeKeys and nativeKeysIn.

.internal/baseKeys.js

@@ -1,5 +1,4 @@
 import isPrototype from './isPrototype.js'
-import nativeKeys from './nativeKeys.js'
 
 /** Used to check objects for own properties. */
 const hasOwnProperty = Object.prototype.hasOwnProperty
@@ -13,7 +12,7 @@ const hasOwnProperty = Object.prototype.hasOwnProperty
  */
 function baseKeys(object) {
   if (!isPrototype(object)) {
-    return nativeKeys(object)
+    return Object.keys(Object(object))
   }
   const result = []
   for (const key in Object(object)) {

.internal/baseKeysIn.js

@@ -1,6 +1,5 @@
 import isObject from '../isObject.js'
 import isPrototype from './isPrototype.js'
-import nativeKeysIn from './nativeKeysIn.js'
 
 /** Used to check objects for own properties. */
 const hasOwnProperty = Object.prototype.hasOwnProperty
@@ -13,12 +12,17 @@ const hasOwnProperty = Object.prototype.hasOwnProperty
  * @returns {Array} Returns the array of property names.
  */
 function baseKeysIn(object) {
+  const result = []
+  if (object == null) {
+    return result
+  }
   if (!isObject(object)) {
-    return nativeKeysIn(object)
+    for (const key in Object(object)) {
+      result.push(key)
+    }
+    return result
   }
   const isProto = isPrototype(object)
-  const result = []
-
   for (const key in object) {
     if (!(key == 'constructor' && (isProto || !hasOwnProperty.call(object, key)))) {
       result.push(key)

.internal/nativeKeys.js

@@ -1,14 +0,0 @@
-/**
- * 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/nativeKeysIn.js

@@ -1,20 +0,0 @@
-/**
- * This function is like
- * [`Object.keys`](http://ecma-international.org/ecma-262/7.0/#sec-object.keys)
- * except that it includes inherited enumerable properties.
- *
- * @private
- * @param {Object} object The object to query.
- * @returns {Array} Returns the array of property names.
- */
-function nativeKeysIn(object) {
-  const result = []
-  if (object != null) {
-    for (const key in Object(object)) {
-      result.push(key)
-    }
-  }
-  return result
-}
-
-export default nativeKeysIn