This files describes API changes in the book code,
information provided here is intended especially for developers.

=== 10 ===

* The following functions, previously used (exclusively) by upgrade steps are not available
  anymore because of the upgrade cleanup performed for this version. See MDL-51580 for more info:
    - mod_book_migrate_moddata_dir_to_legacy()
    - mod_book_migrate_all_areas()
    - mod_book_migrate_area()
