Called each time the metadata loading fails.
This is primarily due to a pending download of the font.
If a value larger than zero is returned, metadata loader will retry after the given
If zero is returned, metadata loader will retry immediately.
If a value less than 0 is returned, the metadata loader will stop retrying and
EmojiCompat will get into LOAD_STATE_FAILED state.
Note that the retry may happen earlier than you specified if the font provider notifies
that the download is completed.