chromium/chrome/test/data/extensions/app_dot_com_app/manifest.json

{
  "name": "App Dot Com: The App",
  "version": "0.1",
  "manifest_version": 2,
  "app": {
    "launch": {
      "container": "tab",
      "web_url": "http://app.com/"
    },
    "urls": [ "http://app.com/" ]
  }
}