Comment 10 for bug 1848550

Since the Angular code will need the ability to relay requests to our IndexedDB handler, I'm also going to start working on that. I'll open a separate bug.

Fortunately, we don't need to reimplement the lovefield/indexeddb parts, just the shared worker pass-through. It should be a pretty direct port. It's possible implementing the cache clearing can be done quickly, in which case we could use it instead of the login redirect, but I also don't want to hold up progress on this bug.