Await safety uncertain in cache/src/store.js

[erights]

agoric-sdk/packages/cache/src/store.js

Line 82 in a1dedea

updatedState = await getUpdatedState(basisState);

The triage at #6219 currently classifies this as

// TODO FIXME This code should be refactored to make this
// await checkably safe, or to remove it, or to record here
// why it is actually safe.
//
// If we knew that this loop is guaranteed to execute at least once,
// then this await would be safe because "terminal-throw-control-flow".
// But if it might execute zero times, then the stateful code after
// this loop might execute synchronously or asynchronously.

Git blame shows @turadg and @michaelfig as the ones who should probably investigate this, so I'm assigning to them. Feel free to reassign as appropriate of course.