This is a reland of 1b36f1a7. The fix is to not use a video that requires proprietary codecs.

Original change's description:
> Add autoplay parameter to navigations.
>
> Bug: 1131881
> Change-Id: Ia152dc0a76d1f9ad6eff87f74fef2ad17b327b91
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2432755
> Reviewed-by: Scott Violet <sky@chromium.org>
> Commit-Queue: John Abd-El-Malek <jam@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#810932}

Bug: 1131881
Change-Id: I4d791880960a0b1ad3dbaf88ece39c4f1b6c8f25
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2435838
Commit-Queue: John Abd-El-Malek <jam@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Auto-Submit: John Abd-El-Malek <jam@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811388}