Add option to re-run only the tests which failed during last run

Just an idea, but I think its a relatively common case that you only want to re-run the tests which failed during the last run (because you just made some changes to fix them). Today you either end up re-running all tests (which you eventually want to do anyways, but ideally not until after you fix the specific ones that were failing), or you manually specify each of the tests you want to retry which is cumbersome.

No files, tests, or entry points are named in the issue. Begin by reviewing how the Dart test runner records failures and accepts test-selection options; done means a documented option can re-run only tests that failed in the previous run, with coverage for that workflow.

Written by the indexing model from the issue text.