function sortedLastIndex(array, value, iteratee, thisArg) {
      iteratee = iteratee == null ? identity : getCallback(iteratee, thisArg, 1);
      return baseSortedIndex(array, value, iteratee, true);
    }
This method is like `_.sortedIndex` except that it returns the highest
index at which a value should be inserted into a given sorted array in
order to maintain the sort order of the array.

@static
@memberOf _
@category Array
@param {Array} array The array to inspect.
@param {*} value The value to evaluate.
@param {Function|Object|string} [iteratee=_.identity] The function invoked
 per iteration. If a property name or object is provided it is used to
 create a "_.pluck" or "_.where" style callback respectively.
@param {*} [thisArg] The `this` binding of `iteratee`.
@returns {number} Returns the index at which `value` should be inserted
 into `array`.
@example

_.sortedLastIndex([4, 4, 5, 5, 6, 6], 5);
// => 4