Changing the type of a primary_key field in a migration does not update FK columns pointing to it

[Tino de Bruijn]

I ran into this when deciding to change from integers to uuid fields. Any fields pointing to the id of the changed model still had column type "integer" instead of "uuid" (on postgres). I hadn't read ​https://docs.djangoproject.com/en/1.8/howto/writing-migrations/#migrations-that-add-unique-fields, but figured out I needed to deal with the unique/non-null values, so I just wiped the table as it was in the early stage of development.

This probably needs documentation like the one mentioned above and a warning (like #23408) , because now both makemigrations and migrate run without any warnings or errors. But after that the structure is broken.

[Tim Graham]

Duplicate of #25012.