Bisect range: @514906 - @514930, suspect @514912

@514906: cros tryjob --remote tricky-tot-chrome-pfq-informational --pass-through="--chrome_version=ba27610e4f6c4a2b4f02327e265f1b2a19145a0a" --yes
@514911: cros tryjob --remote tricky-tot-chrome-pfq-informational --pass-through="--chrome_version=dd9b1f91d0bfa3924e94c1c70aca199a28eb5db2" --yes
@514912: cros tryjob --remote tricky-tot-chrome-pfq-informational --pass-through="--chrome_version=dd9b1f91d0bfa3924e94c1c70aca199a28eb5db2" --yes
@514929: cros tryjob --remote tricky-tot-chrome-pfq-informational --pass-through="--chrome_version=293209f8d033161f4afafc504bd15d0b631167d8" --yes

tryjob results:
https://uberchromegw.corp.google.com/i/chromiumos.tryserver/waterfall?committer=stevenjb@chromium.org&builder=chrome_pfq_informational

https://chromium-review.googlesource.com/757767 is a potential suspect within the range.

Added to "bisect":
@514907: cros tryjob --remote tricky-tot-chrome-pfq-informational --pass-through="--chrome_version=4b10171dd66716d4074d35f1debd98e363cec86b" --yes

Ugh, I forgot to add --hwtest. Restarting bisect.

+Pawel who owns video

likely mine at @514907.  Looking into it now.

tspez@ - any progress on your investigation? The last batch of tryjobs pretended to run HWTests but did not actually :( (filed  issue 783490 )

If you think your CL is likely and reverting won't be too awful, it would be nice to get a green PFQ run tonight, but we can also wait for tomorrow.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/064f38b9f525bc68c3496c141740ab95231ed829

commit 064f38b9f525bc68c3496c141740ab95231ed829
Author: Tom Sepez <tsepez@chromium.org>
Date: Fri Nov 10 00:57:16 2017

Speculative fix for  bug 783312 

The change at @514907 appears to have subtly changed the logic,
so mimic the GetGpuPreSandboxHook() flow as existed in the old
code at

https: //chromium-review.googlesource.com/c/chromium/src/+/757767/4/content/gpu/gpu_sandbox_hook_linux.cc
Bug:  783312 
Change-Id: I14996782de9fc469d3e31e7f1ba46ec353922710
Reviewed-on: https://chromium-review.googlesource.com/761838
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#515389}
[modify] https://crrev.com/064f38b9f525bc68c3496c141740ab95231ed829/content/gpu/gpu_sandbox_hook_linux.cc

Looking at 
https://uberchromegw.corp.google.com/i/chromeos.chrome/builders/tricky-tot-chrome-pfq-informational
https://uberchromegw.corp.google.com/i/chromeos.chrome/builders/caroline-tot-chrome-pfq-informational

Both have a string of green runs following the landing of this patch, please re-open if my analysis is off.

Passed on latest builds: https://stainless.corp.google.com/search?view=matrix&row=board&col=build&first_date=20171111&last_date=20181117&test=video_ChromeHWDecodeUsed&board=tricky%7Ccaroline%7Clumpy%7Cpeppy&exclude_cts=false&exclude_not_run=false&exclude_non_release=true&exclude_au=true&exclude_acts=true&exclude_retried=true&exclude_non_production=true