[packages] Test infra: sub-packages are not supported in test exclusion config files #191447

flutter/packages CI test infra uses "test exclusion" files that can be used to exclude tests for a certain package.

See for example exlude_native_unit_android.yaml which excludes package:espresso from Android unit testing.

However, the exclusion logic only works for top-level packages. Any sub-package (e.g. material_ui/tool/gen_defaults) will inherit its parent exclusion status here.

I believe sub-packages can still be excluded via a dart_test.yaml file in their sub-directory, so fixing this isn't too high of a priority. However, it would be good to document this at least in the exclude files since I spent quite a bit of time trying to figure out why it wasn't working.