livechat: port tests to new api

/cc @ianstormtaylor getting this error on the last 2 tests, where `true` is not being converted to `'true'`, any ideas? what is the desired behavior / what should we do here?

```js
Error: Expected "stub" to be called with "[
  [
    {
      "name": "trait",
      "value": "true"
    }
  ]
]", 
but it was called with "[
  [
    {
      "name": "trait",
      "value": true
    }
  ]
]".
    at module.exports.exports (http://localhost:4202/build/build.js:260:9)
    at Analytics.analytics.called (http://localhost:4202/build/build.js:21581:5)
    at Context.<anonymous> (http://localhost:4202/build/build.js:7807:19)
    at Test.require.register.Runnable.run (http://localhost:4202/test/mocha.js:4212:32)
    at Runner.require.register.Runner.runTest (http://localhost:4202/test/mocha.js:4584:10)
    at http://localhost:4202/test/mocha.js:4630:12
    at next (http://localhost:4202/test/mocha.js:4510:14)
    at http://localhost:4202/test/mocha.js:4519:7
    at next (http://localhost:4202/test/mocha.js:4463:23)
    at http://localhost:4202/test/mocha.js:4482:7
```