[web-db] restore database Safari support

Summary:
Safari bugs are fixed in the rest of the stack.
(context)

Depends on D8124

Test Plan: Test everything end-to-end on Safari (clearing content on logout, init on login, draft persistence, etc.)

Reviewers: michal, tomek

Reviewed By: tomek

Subscribers: ashoat

Differential Revision: https://phab.comm.dev/D8125