viz: Report how far ahead invalid presentation timestamps are.

On android, it turns out the presentation timestamp coming from the
driver can be from the future. Report how far ahead in the future
these timestamps are.

BUG=894440

Change-Id: Ic9bf5620721de3279e8b74277273e8db63da0842
Reviewed-on: https://chromium-review.googlesource.com/c/1294193
Commit-Queue: Sadrul Chowdhury <sadrul@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Reviewed-by: Mark Pearson <mpearson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#601737}
2 files changed