@Override
        public ModelLoader<Integer, ParcelFileDescriptor> build(Context context, GenericLoaderFactory factories) {
            return new FileDescriptorResourceLoader(context, factories.buildModelLoader(Uri.class,
                    ParcelFileDescriptor.class));
        }
The default factory for {@link FileDescriptorResourceLoader}s.
core/src/main/java/com/bumptech/glide/load/model/file_descriptor/FileDescriptorResourceLoader.java