When bug 810205 is fixed, the fix for this could be in file_operation_manager.js:

In FileOperationManager.prototype.serviceDeleteTask_, add the following code or similar:

          var deletedFile = task.entries[0];
          var volumeEntries = this.volumeManager_.volumeInfoList;
          for (var i = 0; i < volumeEntries.length; i++) {
            // Check if we deleted the archive file, or any ancestor directory.
            if (util.isSamePath(deletedFile.path, volumeEntries.entry(i).source_path) || util.isPathPrefixOf(volumeEntries.entry(i).source_path, deletedFile.path)) {
              // Unmount the volume here.
            }
          }

Adding this as P3 to M67 since it becomes trivial once issue 805266 is solved.

 Issue 453273  has been merged into this issue.

Hi Noel, assigning to you as new owner of Zip, I've done some work on these so we can catch up about them if needed.

No, I just know how to spell zip, thanks for asking. 

amistry@ you wanna try one of these?  See #4, not sure whether it's a useful hint or not these days.

And send it back for re-assignment if you feel that way too.

It's tricky to fix with the FSP and so many layers involved.

I think the repro steps are unlikely to happen in normal day-to-day usage. It's an edge case and I think this should be low priority.