File type migration has moved to hidden submodule

In the past, Media had declared its own file types which were later moved to the File Entity module and renamed. In order to provide an upgrade path between the legacy Media file types and the new File Entity file types, the Media module would check if there are file types that need migration and enabled a user interface which facilitated the migration.

In order to improve performance and streamline the Media module, the legacy file type migration code and user interface has been moved into a hidden submodule. The hidden submodule will be automatically enabled by the Media module during an update function if it detects that there are file types that need migration. Once administrators have migrated all of the legacy file types, they will be prompted to disable and uninstall the module.

The file type migration module is not required for new sites and will not appear on the modules page.