[autotest] Bump stable to R31-4731.62.0

TEST=None
BUG=chromium:319006

Change-Id: I6bbeb48ab8202edd4eb7dc2b15682a16447a5488
Reviewed-on: https://chromium-review.googlesource.com/177139
Reviewed-by: Simran Basi <sbasi@chromium.org>
Commit-Queue: Alex Miller <milleral@chromium.org>
Tested-by: Alex Miller <milleral@chromium.org>
1 file changed