The reason for revert was the new navigation timing test expectations
(that got commited right before the original change) had a FAIL
expectation for the particular event order that this change was fixing.

Original change's description:
> Don't adjust the NavigationTimings on redirects
>
> We adjust the timings in WebDocumentLoaderImpl::UpdateNavigation(),
> shouldn't update in each AddRedirect() (which is called in a batch
> way after all the redirects are handled in the browser process with PlzNavigate,
> adjusting timings there with current timestamp is totally wrong)
>
> R=​ksakamoto,arthursonzogni
>
> Bug: 813889
> Change-Id: I3a57d3fdf1833c300feb5ee61737b64cece0946b
> Reviewed-on: https://chromium-review.googlesource.com/974673
> Reviewed-by: Kunihiko Sakamoto <ksakamoto@chromium.org>
> Commit-Queue: Kinuko Yasuda <kinuko@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#546001}

Bug: 813889
Change-Id: I6f5c0ba1196fa1dd52225036820b29a95569ac21
Reviewed-on: https://chromium-review.googlesource.com/981913
Reviewed-by: Kunihiko Sakamoto <ksakamoto@chromium.org>
Commit-Queue: Kinuko Yasuda <kinuko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#546365}