Bump to v3.3.1.

lodash.callback/README.md

@@ -1,4 +1,4 @@
-# lodash.callback v3.3.0
+# lodash.callback v3.3.1
 
 The [modern build](https://github.com/lodash/lodash/wiki/Build-Differences) of [lodash’s](https://lodash.com/) `_.callback` exported as a [Node.js](http://nodejs.org/)/[io.js](https://iojs.org/) module.
 
@@ -17,4 +17,4 @@ In Node.js/io.js:
 var callback = require('lodash.callback');
 ```
 
-See the [documentation](https://lodash.com/docs#callback) or [package source](https://github.com/lodash/lodash/blob/3.3.0-npm-packages/lodash.callback) for more details.
+See the [documentation](https://lodash.com/docs#callback) or [package source](https://github.com/lodash/lodash/blob/3.3.1-npm-packages/lodash.callback) for more details.

lodash.callback/index.js

@@ -1,5 +1,5 @@
 /**
- * lodash 3.3.0 (Custom Build) <https://lodash.com/>
+ * lodash 3.3.1 (Custom Build) <https://lodash.com/>
  * Build: `lodash modern modularize exports="npm" -o ./`
  * Copyright 2012-2015 The Dojo Foundation <http://dojofoundation.org/>
  * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
@@ -62,7 +62,7 @@ function isObjectLike(value) {
  */
 function callback(func, thisArg, guard) {
   if (guard && isIterateeCall(func, thisArg, guard)) {
-    thisArg = null;
+    thisArg = undefined;
   }
   return isObjectLike(func)
     ? matches(func)

lodash.callback/package.json

@@ -1,6 +1,6 @@
 {
   "name": "lodash.callback",
-  "version": "3.3.0",
+  "version": "3.3.1",
   "description": "The modern build of lodash’s `_.callback` as a module.",
   "homepage": "https://lodash.com/",
   "icon": "https://lodash.com/icon.svg",