public Target<TranscodeType> preload() {
        return preload(Target.SIZE_ORIGINAL, Target.SIZE_ORIGINAL);
    }
Preloads the resource into the cache using {@link Target#SIZE_ORIGINAL} as the target width and height.
Equivalent to calling {@link #preload(int, int)} with {@link Target#SIZE_ORIGINAL} as the width and height.

@see #preload(int, int)

@return A {@link Target} that can be used to cancel the load via
       {@link Glide#clear(Target)}.
core/src/main/java/com/bumptech/glide/GenericRequestBuilder.java