Bundle re-prompts for previously allowed files

[tomayac]

Related to https://github.com/WICG/file-system-access/issues/297, where permanent permission to files and folders is discussed, another option for apps dealing with multiple files or folders that now have to show a re-prompt individually for each item would be to batch those re-prompts.

• Present: (For each file individually)

  Let site view foo1.txt? example.com will be able to view foo1.txt until you close all tabs for this site

• Proposed: (Once batched for all files)

  Let site view previously opened files? example.com will be able to view the following files until you close all tabs for this site: foo1.txt, foo2.txt, foo3.txt

[ddumont]

or just don't prompt...

[a-sully]

Closing in favor of #297. We're planning to make permissions persisted per-site rather than per-file. There's some more nuance here which I'll provide on the other issue, but this will have the effect of batching permissions for files the site previously had access to