Revert the revert of the flow analysis workaround  (dart-lang/source_span#61)

* Revert "Prep to release 1.8.0-nullsafety.1"

This reverts commit d851af11e5c521e3210ae2df2b32adeadd263cdc.

* update pubspec/changelog
4 files changed
tree: ec5166ab8b79ce4d9dab162b153eaf384b08858d
  1. pkgs/