Filed by sheriff-o-matic@appspot.gserviceaccount.com on behalf of gab@chromium.org

webkit_layout_tests failing on chromium.webkit/WebKit Linux Trusty Leak

Builders failed on: 
- WebKit Linux Trusty Leak: 
  https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Linux%20Trusty%20Leak

Latest Error:
  Traceback (most recent call last):
    _RunStoryAndProcessErrorIfNeeded at /b/s/w/ir/third_party/catapult/telemetry/telemetry/internal/story_runner.py:147
      test.DidRunStory(state.platform, results)
    DidRunStory at /b/s/w/ir/third_party/catapult/telemetry/telemetry/web_perf/timeline_based_measurement.py:290
      trace_result, _ = platform.tracing_controller.StopTracing()
    StopTracing at /b/s/w/ir/third_party/catapult/telemetry/telemetry/core/tracing_controller.py:53
      return self._tracing_controller_backend.StopTracing()
    StopTracing at /b/s/w/ir/third_party/catapult/telemetry/telemetry/internal/platform/tracing_controller_backend.py:130
      self._IssueClockSyncMarker()
    _IssueClockSyncMarker at /b/s/w/ir/third_party/catapult/telemetry/telemetry/internal/platform/tracing_controller_backend.py:234
      self._RecordIssuerClockSyncMarker)
    RecordClockSyncMarker at /b/s/w/ir/third_party/catapult/telemetry/telemetry/internal/platform/tracing_agent/chrome_tracing_agent.py:178
      raise ChromeClockSyncError('Cannot issue clock sync. No devtools clients')
  ChromeClockSyncError: Cannot issue clock sync. No devtools clients

@https://logs.chromium.org/v/?s=chromium%2Fbb%2Fchromium.mac%2FMac10.11_Tests%2F23413%2F%2B%2Frecipes%2Fsteps%2Ftelemetry_perf_unittests_on_Mac-10.11%2F0%2Fstdout