spawn_shutdown_test fails on app_jitk-linux-debug-x64, app_jitk-linux-release-x64 bots

[aam]

from buildbot logs

--- Command "app_jit" (took 04.000614s):
DART_CONFIGURATION=ReleaseX64 out/ReleaseX64/dart --snapshot=/b/s/w/ir/out/ReleaseX64/generated_compilations/app_jitk-linux-release-x64/runtime_tests_vm_dart_2_spawn_shutdown_test/out.jitsnapshot --snapshot-kind=app-jit --enable-asserts --ignore-unrecognized-flags --packages=/b/s/w/ir/.packages /b/s/w/ir/runtime/tests/vm/dart_2/spawn_shutdown_test.dart

exit code:
-6

stdout:
Info: Compiling without sound null safety
Starting 50 workers...
Waiting for 0:00:02.000000 before exit...

stderr:
===== CRASH =====
si_signo=Segmentation fault(11), si_code=1, si_addr=0x648
version=2.15.0-edge.bda70c84892923769c40a131886d6e70fadc99cb (be) (Thu Sep 2 14:14:35 2021 +0000) on "linux_x64"
pid=2240, thread=2256, isolate_group=(nil)((nil)), isolate=(nil)((nil))
isolate_instructions=0, vm_instructions=55722dfdd5a0
  pc 0x000055722e1a76ee fp 0x00007f7e894fec70 dart::Message::~Message()+0xae
  pc 0x000055722e109167 fp 0x00007f7e894fec90 dart::IsolateSpawnState::~IsolateSpawnState()+0x77
  pc 0x000055722e10b965 fp 0x00007f7e894fed00 out/ReleaseX64/dart+0x1e32965
  pc 0x000055722e2cbea8 fp 0x00007f7e894fed80 dart::ThreadPool::WorkerLoop(dart::ThreadPool::Worker*)+0x148
  pc 0x000055722e2cc2dc fp 0x00007f7e894fedb0 dart::ThreadPool::Worker::Main(unsigned long)+0x5c
  pc 0x000055722e244df8 fp 0x00007f7e894fee70 out/ReleaseX64/dart+0x1f6bdf8
-- End of DumpStackTrace

--- Re-run this test:
python3 tools/test.py -n app_jitk-linux-release-x64 vm/dart_2/spawn_shutdown_test

[aam]

Fixed in https://dart.googlesource.com/sdk/+/eab69f12f86119b002b390ea02e16601953d482e

[dcharkes]

This started failing again on [gardening] Ensure we have an active isolate group when destroying IsolateSpawnState...[vm/compiler] Make closures have no context if no variables are closed over. cc @mkustermann.

--- Command "app_jit" (took 44.000694s):
DART_CONFIGURATION=DebugX64 out/DebugX64/dart --snapshot=/b/s/w/ir/out/DebugX64/generated_compilations/app_jitk-linux-debug-x64/runtime_tests_vm_dart_2_spawn_shutdown_test.dart_1/out.jitsnapshot --snapshot-kind=app-jit --enable-asserts --no-enable-isolate-groups --ignore-unrecognized-flags --packages=/b/s/w/ir/.packages /b/s/w/ir/runtime/tests/vm/dart_2/spawn_shutdown_test.dart

exit code:
-6

stdout:
Info: Compiling without sound null safety
Starting 50 workers...
Waiting for 0:00:02.000000 before exit...

stderr:
../../runtime/lib/isolate.cc: 823: error: expected: IsolateGroup::Current() == state_->isolate_group()
version=2.15.0-edge.462eb6a1054f20e0454dca1daa2ee6f805f50a2c (be) (Fri Sep 3 13:15:57 2021 +0000) on "linux_x64"
pid=22756, thread=23597, isolate_group=(nil)((nil)), isolate=(nil)((nil))
isolate_instructions=0, vm_instructions=560ce91690e0
  pc 0x0000560ce956258c fp 0x00007febc05feac0 dart::Profiler::DumpStackTrace(void*)+0x7c
  pc 0x0000560ce9169294 fp 0x00007febc05feba0 dart::Assert::Fail(char const*, ...) const+0x84
  pc 0x0000560ce931b62e fp 0x00007febc05febf0 out/DebugX64/dart+0x201262e
  pc 0x0000560ce931b3b9 fp 0x00007febc05fec30 out/DebugX64/dart+0x20123b9
  pc 0x0000560ce961aecb fp 0x00007febc05fecd0 dart::ThreadPool::WorkerLoop(dart::ThreadPool::Worker*)+0x1fb
  pc 0x0000560ce961b867 fp 0x00007febc05fed20 dart::ThreadPool::Worker::Main(unsigned long)+0x147
  pc 0x0000560ce9559734 fp 0x00007febc05fee70 out/DebugX64/dart+0x2250734
-- End of DumpStackTrace

--- Re-run this test:
python3 tools/test.py -n app_jitk-linux-debug-x64 vm/dart_2/spawn_shutdown_test/1

log: https://dart-ci.appspot.com/log/app-kernel-linux-debug-x64/app_jitk-linux-debug-x64/9222/vm/dart_2/spawn_shutdown_test/1

[mkustermann]

Have uploaded a fix in https://dart-review.googlesource.com/c/sdk/+/212584