title: setRouteIndex not working in google map direction JS api v3
body: <p>according to <a href="https://developers.google.com/maps/documentation/javascript/reference#DirectionsRenderer" rel="nofollow">this</a>,  directionRenderer object's method <strong>setRouteIndex()</strong> should Set the (zero-based) index of the route in the DirectionsResult object to render.</p>
  
  <p>here is what i have done:</p>
  
  <pre><code>directionsService.route(request, function(response, status) {
                      if (status == google.maps.DirectionsStatus.OK) {
                          directionsDisplay.setRouteIndex(1);
                          console.log(directionsDisplay.getRouteIndex());
                          directionsDisplay.setDirections(response);
                          console.log(directionsDisplay.getRouteIndex());
  
  } });
  </code></pre>
  
  <p>i know there are <strong>3</strong> alternative routes the query i am doing with. here, first <code>console.log(directionsDisplay.getRouteIndex());</code> gives route no. <strong>1</strong>, thats okay , but after the excecution of <code>setDirections</code>, the secong log gives the value 0!. that means the first route. i have enabled, alternative routes, <strong>provideRouteAlternatives:true</strong>, i also initiated the object like this:</p>
  
  <pre><code>var rendererOptions = {
       routeIndex:1 
      }
  directionsDisplay = new google.maps.DirectionsRenderer(rendererOptions);
  </code></pre>
  
  <p>But it still shows the route no. 0, not number 1. here is my <a href="http://ataur.net/MAP/direction.php" rel="nofollow">webpage</a>, please do check the source. thanks in advance.</p>