chrome/test/data/extensions/browsertest/browser_action_popup/manifest.json

{
   "name": "PageAction Test",
  "manifest_version": 2,
   "version": "1.0",
   "browser_action": {
      "default_icon": "icon.png",
      "default_title": "MyExtensionActionTitle",
      "popup": "a_popup.html"
   }
}