We can reduce Math.round(v) to a sequence of

  let i = Float64RoundUp(v);
  let r = i - v;
  return r > 0.5 ? 1.0 + i : i;

if the target supports the Float64RoundUp machine operator (i.e.
roundsd with RoundUp rounding on Intel processors with SSE4.1).

R=jarin@chromium.org

Review URL: https://codereview.chromium.org/1640393002

Cr-Commit-Position: refs/heads/master@{#33572}