chromium/chrome/test/data/extensions/api_test/preference/onchange/manifest.json

{
  "name" : "Preferences API Test Extension (Events)",
  "version" : "0.1",
  "manifest_version": 2,
  "description" : "Preferences API Test Extension (Events)",
  "permissions": [ "privacy" ],
  "background": {
    "scripts": [ "test.js" ],
    "persistent": false
  }
}