- Restores the old inline code sequence, since the branching version
  doesn't set the NaN high bit.

Bug: v8:10862
Change-Id: Iad8ee47b678cc1c6c04222dd83b2fa588ea9136c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2387557Reviewed-by: Zhi An Ng <zhin@chromium.org>
Commit-Queue: Bill Budge <bbudge@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69656}