[Locally Stored Profiles] Automatically store the profile locally after receiving it from the addon

When perf.html is opened from the Gecko Profiler addon, it should take the profile it received, store it in IndexedDB, generate an ID for it, and set the URL to `/local/theGeneratedId/`. And it should support loading the profile from IndexedDB when such a URL is navigated to.

The goal is to survive a browser restart without losing your state, even if you haven't shared the profile publicly.

Some of the problems we'll need to solve as part of this:

* Expiration / quota management
* Wait for symbolication to complete or no?
* How to generate the ID? The web app that stores published profiles generates a hash of the contents, but if we store the profile before we've finished symbolication, then the contents can change; should we keep updating the hash and the URL in that case?

┆Issue is synchronized with this [Jira Task](https://mozilla-hub.atlassian.net/browse/FP-50)