title: Can getBestProvider ever return null?
body: <p>In the following code snippet:</p>
  
  <pre><code> Criteria criteria = new Criteria();
   Criteria.setAccuracy(Criteria.ACCURACY_COARSE);
   criteria.setAltitudeRequired(false);
   criteria.setBearingRequired(false);        
   criteria.setCostAllowed(true);
   criteria.setPowerRequirement(Criteria.NO_REQUIREMENT);         
   String provider = DP.lm.getBestProvider(criteria, true);
  </code></pre>
  
  <p>I've tried to keep the criteria as broad as possible to get any GPS location provider available at all. I need to detect the case when none are available even then. </p>
  
  <p>How can this be handled? Will the getBestProvider call ever return null in such a case? </p>