afdo: revert back to our last known good profile again

As noted in the bug, we recently swapped to a new device for profile
generation. Somehow this materially impacts our profiles.

While this is going to be quite interesting to investigate, it's
probably best to do that while Chrome is humming along happily with a
known good, even if a bit old, profile.

TBR=agrieve@chromium.org

Bug: 992188
Change-Id: I0af6777c248019a71941afec722693c43383d58d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1746200Reviewed-by: George Burgess <gbiv@chromium.org>
Commit-Queue: George Burgess <gbiv@chromium.org>
Cr-Commit-Position: refs/heads/master@{#685501}

chrome/android/profiles/newest.txt

-chromeos-chrome-amd64-78.0.3878.0_rc-r1-merged.afdo.bz2
+chromeos-chrome-amd64-77.0.3864.0_rc-r1-merged.afdo.bz2
\ No newline at end of file