code: function ChromeExtensionFlow(options) {
    BaseBrowserFlow.call(this, options);
    this._authorizationPromise = null;
    this._receiverUrl = chrome.runtime.getURL(
        options.receiverPath || 'asana_oauth_receiver.html');
  }
docs: An Oauth flow that runs in a Chrome browser extension and requests user
  authorization by opening a temporary tab to prompt the user.
  @param {Object} options See `BaseBrowserFlow` for options, plus the below:
  @options {String} [receiverPath] Full path and filename from the base
  directory of the extension to the receiver page. This is an HTML file
  that has been made web-accessible, and that calls the receiver method
  `Asana.auth.ChromeExtensionFlow.runReceiver();`.
  @constructor