message: allow passing initial is_url like hs_url in query params
diff: @@ -282,6 +282,14 @@ export default React.createClass({
  register_hs_url: paramHs,
  });
  }
  + // Set a default IS with query param `is_url`
  + const paramIs = this.props.startingFragmentQueryParams.is_url;
  + if (paramIs) {
  + console.log('Setting register_is_url ', paramIs);
  + this.setState({
  + register_is_url: paramIs,
  + });
  + }
  // a thing to call showScreen with once login completes. this is kept
  // outside this.state because updating it should never trigger a
  