Understanding android virtual device in recipes.

AVD is how flutter launches emulators as defined by CIPD.

• The dependency can be found in https://chrome-infra-packages.appspot.com/p/chromium/tools/android/avd/linux-amd64/
  • Available dependencies appear to be automatically uploaded once per week by the chrome team.
  • At the time of writing, flutter pins the version of avd used.
  • The “versions” supported for a particular dependency come from the source/tools/android/ave/proto directory of the downloaded asset. There is no other way to know support via the cipd tooling.
• To update the cipd dependency change AVD_CIPD_IDENTIFIER in api.py