Replaces Array.prototype.reduce with a for loop.
Replaces Array.prototype.reduce with a for loop.

As this is possibly the hottest code path, this speeds up average total
execution time with about 25%, benchmarking shows.

joegesualdo/chalk,pedroha/chalk,lukeapage/chalk,stevemao/chalk,sterpe/chalk,hughsk/chalk,chalk/chalk,cnuis2cool/chalk,sindresorhus/chalk,rsandor/chalk,yamii/chalk,chalk/chalk