chromium/extensions/test/data/sockets_tcp/api/manifest.json

{
  "name": "chrome.sockets.tcp",
  "manifest_version": 2,
  "version": "0.1",
  "description": "end-to-end browser test for chrome.sockets.tcp API",
  "app": {
    "background": {
      "scripts": ["background.js"]
    }
  },
  "sockets": {
    "tcp":  {"connect": ""}
  }
}