title: Does Glide automatically prevent duplicate calls?
body: <p>Will Glide automatically ignore the second call in the following code? Or will I get 2 separate HTTP requests? Also if it does automatically ignore the second call, is it just "most of the time" or "guaranteed thread-safe always only once"?</p>
  
  <pre><code>Glide.with(context).downloadOnly().load(some_url).into(500, 500);
  Glide.with(context).downloadOnly().load(some_url).into(500, 500);
  </code></pre>