chromium/chromeos/components/test/data/onc/wifi_proxy_pac.onc

{
  "Name": "wifi1",
  "ProxySettings": {
    "Type": "PAC",
    "PAC": "http://pac.foo.com/script.pac"
  },
  "Type": "WiFi",
  "WiFi": {
    "Security": "None"
  }
}