and comparison with a JS implementation using TypedArray

Change-Id: Ifec9c19f23e182db25ad3e54edc3f60c6e6048f4
Reviewed-on: https://chromium-review.googlesource.com/1057729Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Commit-Queue: Théotime Grohens <theotime@google.com>
Cr-Commit-Position: refs/heads/master@{#53177}