Remove multiVal param from _.invert.

lodash.js

@@ -10964,14 +10964,12 @@
     /**
      * Creates an object composed of the inverted keys and values of `object`.
      * If `object` contains duplicate values, subsequent values overwrite property
-     * assignments of previous values unless `multiVal` is `true`.
+     * assignments of previous values.
      *
      * @static
      * @memberOf _
      * @category Object
      * @param {Object} object The object to invert.
-     * @param {boolean} [multiVal] Allow multiple values per key.
-     * @param- {Object} [guard] Enables use as an iteratee for functions like `_.map`.
      * @returns {Object} Returns the new inverted object.
      * @example
      *
@@ -10979,24 +10977,10 @@
      *
      * _.invert(object);
      * // => { '1': 'c', '2': 'b' }
-     *
-     * // with `multiVal`
-     * _.invert(object, true);
-     * // => { '1': ['a', 'c'], '2': ['b'] }
      */
-    function invert(object, multiVal, guard) {
+    function invert(object) {
       return arrayReduce(keys(object), function(result, key) {
-        var value = object[key];
-        if (multiVal && !guard) {
-          if (hasOwnProperty.call(result, value)) {
-            result[value].push(key);
-          } else {
-            result[value] = [key];
-          }
-        }
-        else {
-          result[value] = key;
-        }
+        result[object[key]] = key;
         return result;
       }, {});
     }