@Override
        public String getId() {
            // Both the stream fetcher and the file descriptor fetcher should return the same id.
            if (streamFetcher != null) {
                return streamFetcher.getId();
            } else {
                return fileDescriptorFetcher.getId();
            }
        }
A wrapper model loader that provides both an {@link InputStream} and a
{@link ParcelFileDescriptor} for a given model type by wrapping an
{@link ModelLoader} for {@link InputStream}s for the given model type and an
{@link ModelLoader} for {@link ParcelFileDescriptor} for the given model
type.

@param <A> The model type.
core/src/main/java/com/bumptech/glide/load/model/ImageVideoModelLoader.java