The option is not used by any client at this time and removing it simplifies the
next stack of changes I'll be making on how we compose file systems.
I also don't believe we will necessarily add this back as an option, but instead
it might be that clients requriing hermeticity will provide a custom file system
that helps with that.
Change-Id: I401efb042920d234382b6c041b13d40ffae5c908
Reviewed-on: https://dart-review.googlesource.com/56462
Commit-Queue: Peter von der Ahé <ahe@google.com>
Reviewed-by: Peter von der Ahé <ahe@google.com>
Sigmund Cherem
9b44fc39c8