title: get google map zoom level when using fitBounds
body: <p>I want to get google map current zoom level, it gives me undefined error, I think because I don't use explicit zoom level in my map creation options, rather I use map.fitBounds, how can I get google map zoom level when I'm using map.fitBounds?</p>
  
  <p>this is my code summary:</p>
  
  <pre><code>var mapOptions = { mapTypeId: google.maps.MapTypeId.ROADMAP };
  
  map =  new google.maps.Map(document.getElementById("map_canvas"), mapOptions);
  
  map.fitBounds(bounds);
  map.panToBounds(bounds);
  </code></pre>
  
  <p>now, when I want to use map.getZoom(), I get undefined, it seems that getZoom only returns explicitly set zoom levels</p>