* Roll back three Dart SDK rolls
Revert "Roll src/third_party/dart 75ee523f91..4cff5a4fd6 (6 commits)"
Revert "Roll src/third_party/dart 5ddd157809..75ee523f91 (19 commits)"
Revert "Roll src/third_party/dart c92d5ca288..5ddd157809 (153 commits)"
`pub upgrade` appears to fail 100% reproducibly on broken on Windows.
This rollback rolls back both what appears to be the breaking roll (61fc178)
and the following roll.
This reverts commit 0053c1d5064931d7a690b3d8888d15d72785a079.
This reverts commit 1cf6b8b64d42aefcbc6e7d78a2e6df706962751a.
This reverts commit 61fc1786fd98f48ee355f800cf5d7aef0fff985b.
* Revert "Revert "Revert "Remove unnecessary entry-point closurization. (#7827)" (#7876)" (#7904)"
This reverts commit 93eeb48baee5c24047a4a3cf5b1db234ecc48683.