title: Glide crashes app on loading an animated jpg
body: <p>So, I'm loading photos from imgur using Glide with the code below.</p>
  
  <pre><code>try {
      ViewTarget viewTarget = new ViewTarget&lt;SubsamplingScaleImageView, BitmapDrawable&gt;(image_view) {
          @Override
          public void onResourceReady(BitmapDrawable bitmap, Transition&lt;? super BitmapDrawable&gt; transition) {
              this.view.setImage(ImageSource.bitmap(bitmap.getBitmap()));
          }
      };
  
      GlideApp.with(this).load(post_to_show.getUrl()).into(viewTarget);
  } catch (ClassCastException e){}
  </code></pre>
  
  <p>where SubsamplingScaleImageView is - well - a Custom ImageView extending View.
  But it doesn't matter here.</p>
  
  <p>It's working fine, until I try loading something like <a href="https://i.imgur.com/DyPF53S.jpg" rel="nofollow noreferrer">this</a></p>
  
  <p>It has a .jpg extension, but it's a gif.</p>
  
  <p>I get this error:</p>
  
  <blockquote>
    <p>E/AndroidRuntime: FATAL EXCEPTION: main
                                                                       Process: me.ekhaled667.ridit, PID: 6202
                                                                       java.lang.ClassCastException: com.bumptech.glide.load.resource.gif.GifDrawable cannot be cast to android.graphics.drawable.BitmapDrawable
                                                                           at me.ekhaled667.ridit.PostFragment$1.onResourceReady(PostFragment.java:257)
                                                                           at com.bumptech.glide.request.SingleRequest.onResourceReady(SingleRequest.java:579)
                                                                           at com.bumptech.glide.request.SingleRequest.onResourceReady(SingleRequest.java:549)
                                                                           at com.bumptech.glide.load.engine.EngineJob.handleResultOnMainThread(EngineJob.java:218)
                                                                           at com.bumptech.glide.load.engine.EngineJob$MainThreadCallback.handleMessage(EngineJob.java:324)
                                                                           at android.os.Handler.dispatchMessage(Handler.java:98)
                                                                           at android.os.Looper.loop(Looper.java:163)
                                                                           at android.app.ActivityThread.main(ActivityThread.java:6348)
                                                                           at java.lang.reflect.Method.invoke(Native Method)
                                                                           at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:880)
                                                                           at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:770)</p>
  </blockquote>
  
  <p>First: why wasn't it caught as an exception?</p>
  
  <p>Second: How can I possibly go around this, or put another way, know that this is a gif not a jpg and load it properly?</p>