Pigeon doesn't depend on Flutter but it is listed as a dependency in the pubspec.yaml. This causes 2 problems:

1. On new versions of flutter it causes run_tests.sh to fail since it uses dart to run tests, but the tests will error out saying you need to run flutter instead
2. The pub.dev page says it is "unidentified" since it doesn't list any platforms

Our options are to:

1. Fully embrace the dependency on flutter despite the fact there is no actual runtime dependency on flutter
2. Rip out the dependency on flutter

Ripping it out is technically correct but if we do that it will confuse different ci steps that rely on that dependency to be there. Maybe it is a good idea to fully embrace the dependency on flutter in order to control access to new flutter features. In the past we've just always conformed to the platform channel API which is pretty stable so no version check of flutter was necessary.

cc @stuartmorgan