chromium/chrome/test/data/extensions/test_default_apps/external_extensions.json

{
  "kbmnembihfiondgfjekmnmcbddelicoi": {
    "external_crx": "test.crx",
    "external_version": "1.0.0.0",
    "web_app_migration_flag": "MigrateDefaultChromeAppToWebAppsNonGSuite"
  }
}