Making a noop edit to tools/perf/benchmarks/system_health_smoke_test.py like adding a comment results in the following presubmit failure upon uploading:

Running presubmit upload checks ...

** Presubmit Messages **
Missing OWNER reviewers for these files:
    tools/perf/benchmarks/system_health_smoke_test.py

Suggested OWNERS: (Use "git-cl owners" to interactively select owners.)
    kouhei@chromium.org is commented as:
      For page_cycler and loading benchmarks related changes. (at tools/perf)

** Presubmit Warnings **
Pylint (266 files using ['--disable=cyclic-import'] on 40 cores) (3.35s) failed
************* Module benchmarks.system_health_unittest
E: 15, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module benchmarks.benchmark_unittest
E: 18, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module contrib.cluster_telemetry.multipage_skpicture_printer
E: 13, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module benchmarks.benchmark_smoke_unittest
E: 22, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module benchmarks.system_health_smoke_test
E: 22, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module contrib.cluster_telemetry.skpicture_printer
E: 14, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module core.benchmark_finders
E: 14, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module measurements.measurement_smoke_test
E: 16, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module core.find_dependencies
E: 18, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module page_sets
E: 12, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module core.perf_data_generator
E: 28, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module page_sets.system_health.system_health_stories
E: 13, 0: No name 'discover' in module 'py_utils' (no-name-in-module)
************* Module profile_creators.profile_generator
E: 22, 0: No name 'discover' in module 'py_utils' (no-name-in-module)


** Presubmit ERRORS **
Validating Perf JSON configs failed.

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Traceback (most recent call last):
  <module> at /usr/local/google/home/alancutter/repos/chromium2/src/tools/perf/generate_perf_data:8
    from core import perf_data_generator
  <module> at /usr/local/google/home/alancutter/repos/chromium2/src/tools/perf/core/perf_data_generator.py:28
    from py_utils import discover
ImportError: cannot import name discover

Locals:
  __builtins__        : {'bytearray': <type 'bytearray'>, 'IndexError': <type 'exceptions.IndexError'>, 'all': <built-in function all>, 'help': Type help() for interactive help, or help(object) for help about object., 'vars': <built-in function vars>, 'SyntaxError': <type 'exceptions.SyntaxError'>, 'unicode': <type 'unicode'>, 'UnicodeDecodeError': <type 'exceptions.UnicodeDecodeError'>, 'memoryview': <type 'memoryview'>, 'isinstance': <built-in function isinstance>, 'copyright': Copyright (c) 2001-2014 Python Software Foundati ... unction callable>, 'ZeroDivisionError': <type 'exceptions.ZeroDivisionError'>, 'eval': <built-in function eval>, '__debug__': True, 'IndentationError': <type 'exceptions.IndentationError'>, 'AssertionError': <type 'exceptions.AssertionError'>, 'classmethod': <type 'classmethod'>, 'UnboundLocalError': <type 'exceptions.UnboundLocalError'>, 'NotImplementedError': <type 'exceptions.NotImplementedError'>, 'AttributeError': <type 'exceptions.AttributeError'>, 'OverflowError': <type 'exceptions.OverflowError'>} (truncated)
  __doc__             : None
  __file__            : None
  __name__            : None
  __package__         : None
  __warningregistry__ : None
  argparse            : None
  benchmark_module    : None
  collections         : None
  csv                 : None
  decorators          : None
  json                : None
  os                  : None
  path_util           : None
  re                  : None
  sets                : None
  sys                 : None
***************

Validating story expectation data failed.

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Traceback (most recent call last):
  <module> at /usr/local/google/home/alancutter/repos/chromium2/src/tools/perf/validate_story_expectation_data:8
    from core import story_expectation_validator
  <module> at /usr/local/google/home/alancutter/repos/chromium2/src/tools/perf/core/story_expectation_validator.py:8
    from core import benchmark_finders
  <module> at /usr/local/google/home/alancutter/repos/chromium2/src/tools/perf/core/benchmark_finders.py:14
    from py_utils import discover
ImportError: cannot import name discover

Locals:
  __builtins__     : {'bytearray': <type 'bytearray'>, 'IndexError': <type 'exceptions.IndexError'>, 'all': <built-in function all>, 'help': Type help() for interactive help, or help(object) for help about object., 'vars': <built-in function vars>, 'SyntaxError': <type 'exceptions.SyntaxError'>, 'unicode': <type 'unicode'>, 'UnicodeDecodeError': <type 'exceptions.UnicodeDecodeError'>, 'memoryview': <type 'memoryview'>, 'isinstance': <built-in function isinstance>, 'copyright': Copyright (c) 2001-2014 Python Software Foundati ... unction callable>, 'ZeroDivisionError': <type 'exceptions.ZeroDivisionError'>, 'eval': <built-in function eval>, '__debug__': True, 'IndentationError': <type 'exceptions.IndentationError'>, 'AssertionError': <type 'exceptions.AssertionError'>, 'classmethod': <type 'classmethod'>, 'UnboundLocalError': <type 'exceptions.UnboundLocalError'>, 'NotImplementedError': <type 'exceptions.NotImplementedError'>, 'AttributeError': <type 'exceptions.AttributeError'>, 'OverflowError': <type 'exceptions.OverflowError'>} (truncated)
  __doc__          : None
  __file__         : None
  __name__         : None
  __package__      : None
  benchmark_module : None
  imp              : None
  inspect          : None
  os               : None
  path_util        : None
  perf_benchmark   : None
  sys              : None
***************

Presubmit checks took 8.0s to calculate.