title: How to catch the error when angularjs has 400 (Bad Request)?
body: <p>GET url 400 (Bad Request) or any get url error. How to ignore the error?</p>
  
  <pre><code>$http.get(res.getQNUrl(domain, key, "exif"))
  .success(function(data){
      $scope.imageExifMap[key] = data
  }).error(entry.onError)
  </code></pre>
  
  <p>e.g.: <code>http://tratao-public.qiniudn.com/c851b00c127146997f017bb899bb9bb8.jpg?exif</code>
  it will get
  <code>{"error":"no exif data"}</code></p>
  
  <p>Chrome get error: <code>GET http://tratao-public.qiniudn.com/c851b00c127146997f017bb899bb9bb8.jpg?exif 400 (Bad Request)</code></p>