The following stories:
- browse:social:facebook
- browse:news:toi
- browse:social:twitter
- browse:news:cnn
- browse:media:youtube

Have started failing consistently on system_health.common_mobile since build:
https://luci-milo.appspot.com/buildbot/chromium.perf/Android%20Nexus5X%20Perf/88

The exception is a js timeout while navigating between elements in the story, e.g.:

Traceback (most recent call last):
  File "/b/swarming/w/ir/third_party/catapult/telemetry/telemetry/internal/story_runner.py", line 90, in _RunStoryAndProcessErrorIfNeeded
    state.RunStory(results)
  File "/b/swarming/w/ir/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 75, in traced_function
    return func(*args, **kwargs)
  File "/b/swarming/w/ir/third_party/catapult/telemetry/telemetry/page/shared_page_state.py", line 296, in RunStory
    self._current_page.Run(self)
  File "/b/swarming/w/ir/third_party/catapult/telemetry/telemetry/page/__init__.py", line 112, in Run
    self.RunPageInteractions(action_runner)
  File "/b/swarming/w/ir/tools/perf/page_sets/system_health/system_health_story.py", line 138, in RunPageInteractions
    self._DidLoadDocument(action_runner)
  File "/b/swarming/w/ir/tools/perf/page_sets/system_health/browsing_stories.py", line 81, in _DidLoadDocument
    self._NavigateToItem(action_runner, i)
  File "/b/swarming/w/ir/tools/perf/page_sets/system_health/browsing_stories.py", line 41, in _NavigateToItem
    container_selector=self.CONTAINER_SELECTOR)
  File "/b/swarming/w/ir/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 75, in traced_function
    return func(*args, **kwargs)
  File "/b/swarming/w/ir/third_party/catapult/telemetry/telemetry/internal/actions/action_runner.py", line 465, in ScrollPageToElement
    speed_in_pixels_per_second=speed_in_pixels_per_second))
  File "/b/swarming/w/ir/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 75, in traced_function
    return func(*args, **kwargs)
  File "/b/swarming/w/ir/third_party/catapult/telemetry/telemetry/internal/actions/action_runner.py", line 56, in _RunAction
    action.RunAction(self._tab)
  File "/b/swarming/w/ir/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 75, in traced_function
    return func(*args, **kwargs)
  File "/b/swarming/w/ir/third_party/catapult/telemetry/telemetry/internal/actions/scroll_to_element.py", line 85, in RunAction
    self._scroller.RunAction(tab)
  File "/b/swarming/w/ir/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 75, in traced_function
    return func(*args, **kwargs)
  File "/b/swarming/w/ir/third_party/catapult/telemetry/telemetry/internal/actions/scroll.py", line 110, in RunAction
    tab.WaitForJavaScriptCondition('window.__scrollActionDone', timeout=60)
  File "/b/swarming/w/ir/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 75, in traced_function
    return func(*args, **kwargs)
  File "/b/swarming/w/ir/third_party/catapult/telemetry/telemetry/internal/browser/web_contents.py", line 191, in WaitForJavaScriptCondition
    return self._inspector_backend.WaitForJavaScriptCondition(*args, **kwargs)
  File "/b/swarming/w/ir/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py", line 75, in traced_function
    return func(*args, **kwargs)
  File "/b/swarming/w/ir/third_party/catapult/telemetry/telemetry/internal/backends/chrome_inspector/inspector_backend.py", line 293, in WaitForJavaScriptCondition
    e.message + '\n' + debug_message)
TimeoutException: Timed out while waiting 60s for IsJavaScriptExpressionTrue.
https://luci-logdog.appspot.com/v/?s=chrome%2Fbb%2Fchromium.perf%2FAndroid_Nexus5X_Perf%2F88%2F%2B%2Frecipes%2Fsteps%2Fsystem_health.common_mobile_on_Android%2F0%2Fstdout

For some reason screenshots appear all black, e.g. browse:news:toi:
https://console.developers.google.com/m/cloudstorage/b/chrome-telemetry-output/o/profiler-file-id_12-2017-05-23_16-40-5945202.png

CL range:
http://test-results.appspot.com/revision_range?start=473831&end=473887