Chromedriver Win7 is failing since yesterday night.
https://build.chromium.org/p/chromium.chromedriver/builders/Win7

First build that failed : https://build.chromium.org/p/chromium.chromedriver/builders/Win7/builds/21594

Traceback (most recent call last):
  File "E:\b\build\scripts\slave\.recipe_deps\recipe_engine\recipe_engine\run.py", line 374, in _old_run
    recipe_result = recipe_script.run(api, properties)
  File "E:\b\build\scripts\slave\.recipe_deps\recipe_engine\recipe_engine\loader.py", line 98, in run
    self.run_steps, properties, self.PROPERTIES, api=api)
  File "E:\b\build\scripts\slave\.recipe_deps\recipe_engine\recipe_engine\loader.py", line 628, in invoke_with_properties
    **additional_args)
  File "E:\b\build\scripts\slave\.recipe_deps\recipe_engine\recipe_engine\loader.py", line 589, in _invoke_with_properties
    return callable_obj(*props, **additional_args)
  File "E:\b\build\scripts/slave\recipes\chromium.chromedriver.recipe_autogen.py", line 316, in RunSteps
    dispatch_directory[api.properties["buildername"]](api)
  File "E:\b\build\scripts/slave\recipes\chromium.chromedriver.recipe_autogen.py", line 208, in Win7_steps
    result = api.bot_update.ensure_checkout()
  File "E:\b\build\scripts\slave\.recipe_deps\recipe_engine\recipe_engine\recipe_api.py", line 631, in _inner
    return func(*a, **kw)
  File "E:\b\build\scripts\slave\.recipe_deps\depot_tools\recipes\recipe_modules\bot_update\api.py", line 273, in ensure_checkout
    self._last_returned_properties = step_result.json.output.get(
AttributeError: 'NoneType' object has no attribute 'get'

Could someone please look into it? Thanks.