Await safety uncertain in cosmic-swingset/src/chain-main.js

[erights]

agoric-sdk/packages/cosmic-swingset/src/chain-main.js

Line 532 in a1dedea

blockingSend = await launchAndInitializeSwingSet(action);

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.
  //
  // Likely `blockingSend` is not sensitive to whether it is called
  // in the same or a subsequent turn. If that were verified, then
  // this await would be safe because "terminal-control-flow".

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