pkg/dds/test/dap/integration/debug_test flaky -> RuntimeError

[alexmarkov]

The test

pkg/dds/test/dap/integration/debug_test RuntimeError (expected Pass)

is failing on configuration

unittest-asserts-release-win-arm64

00:59 �[32m+15�[0m�[33m ~1�[0m�[31m -1�[0m: debug mode provides a list of threads �[1m�[31m[E]�[0m�[0m

  Expected: 'breakpoint'
    Actual: 'exit'
     Which: is different.
            Expected: breakpoint ...
              Actual: exit
                      ^
             Differ at offset 0
  

  package:matcher/src/expect/expect.dart 149:31        fail
  package:matcher/src/expect/expect.dart 144:3         _expect
  package:matcher/src/expect/expect.dart 56:3          expect
  pkg\dds\test\dap\integration\test_client.dart 947:5  DapTestClientExtension.expectStop
  ===== asynchronous gap ===========================
  pkg\dds\test\dap\integration\debug_test.dart 494:7   main.<fn>.<fn>
  ===== asynchronous gap ===========================
  package:test_api/src/backend/declarer.dart 229:9     Declarer.test.<fn>.<fn>
  ===== asynchronous gap ===========================
  package:test_api/src/backend/declarer.dart 227:7     Declarer.test.<fn>
  ===== asynchronous gap ===========================
  package:test_api/src/backend/invoker.dart 258:9      Invoker._waitForOutstandingCallbacks.<fn>

Full log: https://dart-ci.appspot.com/log/pkg-win-release-arm64/unittest-asserts-release-win-arm64/3126/pkg/dds/test/dap/integration/debug_test

@bkonyi @derekxu16

[derekxu16]

FYI @DanTup, this looks like the same failure as in #56965.

[DanTup]

Yeah, this is the same. Still trying to get to the bottom of it. I repro'd it locally and fixed, but it turned out I must've repro'd it in a different way to what was happening on the bots because the bot still failed.