IndexOutOfBoundsException in GifFrameLoader

I got a crash in GifFrameLoader
```
java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
java.util.ArrayList.get(ArrayList.java:437)
com.bumptech.glide.load.resource.gif.GifFrameLoader.a(SourceFile:282)
com.bumptech.glide.load.resource.gif.GifFrameLoader$b.handleMessage(SourceFile:304)
android.os.Handler.dispatchMessage(Handler.java:102)
android.os.Looper.loopOnce(Looper.java:233)
android.os.Looper.loop(Looper.java:334)
android.app.ActivityThread.main(ActivityThread.java:8551)
java.lang.reflect.Method.invoke(Native Method)
com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:582)
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
```
and the same issue :[GlideWebpDecoder](https://github.com/zjupure/GlideWebpDecoder/issues/100)，this issue has fixed this crash.
can you fix it which is in Glide？