Inconsistency `.reduce` reducer counter argument with `Array` method

[zloirock]

With #211:

[1, 2].reduce((a, e, i) => console.log(i)); // => 1

[1, 2].values().reduce((a, e, i) => console.log(i)); // => 0

[ljharb]

Indeed, the first invocation of a reduce with no initialValue argument must start its "counter" at 1.