This allows you to put iterables into your array literals
and the will get spread into the array.
let x = [0, ...range(1, 3)]; // [0, 1, 2]
This is done by treating the array literal up to the first
spread element as usual, including using a boiler plate
array, and then appending the remaining expressions and rest
expressions.
BUG=v8:3018
LOG=N
Review URL: https://codereview.chromium.org/1125183008
Cr-Commit-Position: refs/heads/master@{#28534}
