Why is this running on chromium.linux? Is this a correctness test?

Disabling test for now https://codereview.chromium.org/2834503002

Re #2: It's a correctness test. Assigning to Ned for triage.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/378a76063f6d98d7b0c84e3e83c8743bdd8421be

commit 378a76063f6d98d7b0c84e3e83c8743bdd8421be
Author: ojan <ojan@chromium.org>
Date: Wed Apr 19 20:03:51 2017

SmoothnessUnitTest/testSmoothness is flaky on linux.

BUG=713260
TBR=sullivan@chromium.org

Review-Url: https://codereview.chromium.org/2834503002
Cr-Commit-Position: refs/heads/master@{#465722}

[modify] https://crrev.com/378a76063f6d98d7b0c84e3e83c8743bdd8421be/tools/perf/measurements/smoothness_unittest.py

  Traceback (most recent call last):
    File "/b/s/w/ir/tools/perf/measurements/smoothness_unittest.py", line 122, in testSmoothness
      self.assertGreater(frame_times[0].GetRepresentativeNumber(), 0)
    File "/b/s/w/ir/third_party/catapult/telemetry/telemetry/value/list_of_scalar_values.py", line 133, in GetRepresentativeNumber
      return _Mean(self.values)
    File "/b/s/w/ir/third_party/catapult/telemetry/telemetry/value/list_of_scalar_values.py", line 63, in _Mean
      return float(sum(values)) / len(values) if len(values) > 0 else 0.0
  TypeError: object of type 'NoneType' has no len()

(https://chromium-swarm.appspot.com/task?id=35a003044482c910&refresh=10&show_raw=1)


This means the scrolling the page sometimes has no frame 

Victor: can you help triaging this since the cause seems to come from Chrome?

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2af8afa73468665ddc6329ffab133bd49635251f

commit 2af8afa73468665ddc6329ffab133bd49635251f
Author: vmiura <vmiura@chromium.org>
Date: Thu May 11 20:44:20 2017

Re-enable smoothness_unittest testSmoothness on Linux.

Test was disabled due to flakyness.  Re-enabling to diagnose current situation.

TBR=sullivan@chromium.org
BUG=713260

Review-Url: https://codereview.chromium.org/2870233002
Cr-Commit-Position: refs/heads/master@{#471063}

[modify] https://crrev.com/2af8afa73468665ddc6329ffab133bd49635251f/tools/perf/measurements/smoothness_unittest.py

I've seen this problem a couple of times in the last few days:
  Trace sizes in bytes: {'traceEvents': 145558, 'tabIds': 36}
  Closing browser (pid=30722) ...
  Browser is closed.
  Traceback (most recent call last):
    File "/b/s/w/ir/tools/perf/measurements/smoothness_unittest.py", line 70, in testSmoothness
      self.assertGreater(frame_times[0].GetRepresentativeNumber(), 0)
    File "/b/s/w/ir/third_party/catapult/telemetry/telemetry/value/list_of_scalar_values.py", line 133, in GetRepresentativeNumber
      return _Mean(self.values)
    File "/b/s/w/ir/third_party/catapult/telemetry/telemetry/value/list_of_scalar_values.py", line 63, in _Mean
      return float(sum(values)) / len(values) if len(values) > 0 else 0.0
  TypeError: object of type 'NoneType' has no len()

Example build log:
https://uberchromegw.corp.google.com/i/chromium.chromiumos/builders/linux-chromeos-rel/builds/4466

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/423581b41cc8544e7e6c2aa92c017c90058733eb

commit 423581b41cc8544e7e6c2aa92c017c90058733eb
Author: Joe Downing <joedow@chromium.org>
Date: Wed Jan 24 19:47:18 2018

Disabling flaky smoothness test

This test was re-enabled last year (May 2017) in order to investigate
the flakiness but it appears to still be flaky and is causing several
failures per day in sheriff-o-matic.

TBR=vmiura@chromium.org

BUG=713260

Change-Id: Idefbba7c8b6fa32e1bd75a39fcae422ca9c5d4b9
Reviewed-on: https://chromium-review.googlesource.com/884181
Reviewed-by: Joe Downing <joedow@chromium.org>
Commit-Queue: Joe Downing <joedow@chromium.org>
Cr-Commit-Position: refs/heads/master@{#531650}
[modify] https://crrev.com/423581b41cc8544e7e6c2aa92c017c90058733eb/tools/perf/measurements/smoothness_unittest.py