test_repeat_count, while has a default=100 in the recipe, is set to None for several try jobs and the default seems to be ignored.

As a result flake try jobs end in error since test_repeat_count is None.

For example,

https://build.chromium.org/p/tryserver.chromium.android/builders/android_chromium_variable/builds/335

Also, schedule_flake_try_job_pipeline.py is reading the config that sets test_repeat_count in its legacy format, which is no longer supported.