GifBitmapWrapperTransformation getDrawableFitCenter() {
        return drawableFitCenter;
    }
Returns the {@link BitmapPool} used to temporarily store
{@link Bitmap}s so they can be reused to avoid garbage collections.

<p>
    Note - Using this pool directly can lead to undefined behavior and strange drawing errors. Any
    {@link Bitmap} added to the pool must not be currently in use in any other part of the
    application. Any {@link Bitmap} added to the pool must be removed from the pool before it
    is added a second time.
</p>

<p>
    Note - To make effective use of the pool, any {@link Bitmap} removed from the pool must
    eventually be re-added. Otherwise the pool will eventually empty and will not serve any useful purpose.
</p>

<p>
    The primary reason this object is exposed is for use in custom
    {@link com.bumptech.glide.load.ResourceDecoder}s and {@link com.bumptech.glide.load.Transformation}s. Use
    outside of these classes is not generally recommended.
</p>
core/src/main/java/com/bumptech/glide/Glide.java