Maps in Item frames' markers aren't persistent

Please, refer to MC-1528. (Issue somehow closed with "won't fix" resolution)

Bug is still present in latest verion (1.11)
Easiest way to reproduce:

1. create map and do max zoom out

2. Setup map into frame in some far away chunk (e.g. top left corner of map)

3. Move far from frame (bottom right)

4. Quit game completely.

5. Load gale, check map