function getIndexOf(collection, target, fromIndex) {
      var result = lodash.indexOf || indexOf;
      result = result === indexOf ? baseIndexOf : result;
      return collection ? result(collection, target, fromIndex) : result;
    }
Gets the appropriate "indexOf" function. If the `_.indexOf` method is
customized this function returns the custom method, otherwise it returns
the `baseIndexOf` function. If arguments are provided the chosen function
is invoked with them and its result is returned.

@private
@returns {Function|number} Returns the chosen function or its result.