chromium/chrome/test/data/extensions/api_test/webnavigation/app/manifest.json

{
  "name": "App Test",
  "version": "1",
  "manifest_version": 2,
  "permissions": [
    "background"
  ],
  "app": {
    "launch": {
      "web_url": "http://www.a.com/server-redirect"
    }
  }
}