Error message:

Traceback (most recent call last):
  RunBenchmark at /usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/internal/story_runner.py:369
    expectations=expectations, max_num_values=benchmark.MAX_NUM_VALUES)
  Run at /usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/internal/story_runner.py:234
    _RunStoryAndProcessErrorIfNeeded(story, results, state, test)
  _RunStoryAndProcessErrorIfNeeded at /usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/internal/story_runner.py:126
    state.RunStory(results)
  traced_function at /usr/local/telemetry/src/third_party/catapult/common/py_trace_event/py_trace_event/trace_event_impl/decorators.py:75
    return func(*args, **kwargs)
  RunStory at /usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/page/shared_page_state.py:300
    self._current_page.Run(self)
  Run at /usr/local/telemetry/src/third_party/catapult/telemetry/telemetry/page/__init__.py:99
    self.RunPageInteractions(action_runner)
  RunPageInteractions at /usr/local/telemetry/src/tools/perf/contrib/cros_benchmarks/tab_switching_stories.py:79
    with cros_utils.KeyboardEmulator(self._cros_remote) as keyboard:
  __enter__ at /usr/local/telemetry/src/tools/perf/contrib/cros_benchmarks/cros_utils.py:181
    self._key_device_name = self._StartRemoteKeyboardEmulator()
  _StartRemoteKeyboardEmulator at /usr/local/telemetry/src/tools/perf/contrib/cros_benchmarks/cros_utils.py:153
    raise RuntimeError('Keyboard property file does not exist.')
RuntimeError: Keyboard property file does not exist.

Locals:
  kbd_prop_filename : '/usr/local/autotest/cros/input_playback/keyboard.prop'
  ret               : 256

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/dc8462fed47f034e93b537d48f0862cb999a5567

commit dc8462fed47f034e93b537d48f0862cb999a5567
Author: Kuo-Hsin Yang <vovoy@chromium.org>
Date: Fri Sep 07 07:59:04 2018

cros_tab_switching: upload keyboard emulator property file

Upload the keyboard property file for keyboard emulator to remove the
dependency to /usr/local/autotest/cros/input_playback/keyboard.prop.

Bug:  chromium:881240 
Change-Id: I65daf0326d9237ac5a904f2966be4e95c6f8e210
Reviewed-on: https://chromium-review.googlesource.com/1209135
Commit-Queue: Vovo Yang <vovoy@chromium.org>
Reviewed-by: Cheng-Yu Lee <cylee@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589452}
[modify] https://crrev.com/dc8462fed47f034e93b537d48f0862cb999a5567/tools/perf/contrib/cros_benchmarks/cros_utils.py
[add] https://crrev.com/dc8462fed47f034e93b537d48f0862cb999a5567/tools/perf/contrib/cros_benchmarks/data/keyboard.prop