Persist Interaction State for tabs

[dus7]

Task/Issue URL: https://app.asana.com/0/0/1208991633646641/f
Tech Design URL: https://app.asana.com/0/481882893211075/1208983861756006/f
CC:

Description:

Adds storage and automatically stores WKWebView's interaction state data for each tab. These are used to restore back/forward history and scroll position on next launch after app was terminated.

Steps to test this PR:

1. Mark yourself as internal user to enable the feature. Restart is required for the flag to have an effect.
2. Open a few tabs, navigate to various links so that navigating back/forward is possible. Scroll can be adjusted.
3. Terminate the app.
4. Verify last opened tab is visible and website is scrolled to (roughly) the same position on the screen.
5. Verify navigation history is available and working properly.
6. Use Fire button. Verify all cache files are being removed. You can check the directory by putting a breakpoint somewhere in TabInteractionStateDiskSource and printing interactionStateCacheLocation or use debug menu to see the list of cache files.
7. Open a few tabs again, enable Automatic Data Clearing.
8. Verify all interaction cache files are removed.

Definition of Done (Internal Only):

• Does this PR satisfy our Definition of Done?

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Internal references:

Software Engineering Expectations
Technical Design Template

[github-actions]

	Warnings
⚠️	PR has more than 500 lines of code changing. Consider splitting into smaller PRs if possible.

Generated by 🚫 dangerJS against 1fabeb0

[brindy]

Nice work. We talked about a couple of things on MM (add feature flag, moving code to extensions) and that looks good too.