Make StopRecur test hardened against move-exception

In some circumstances a StopThread call can occur just before a
move-exception instruction. In this case the stopThread exception can
be cleared unintentionally.

Test: stress --cpu 60
Test: ./test/run-test --host --gcstress 1934
Bug: 67576489
Change-Id: Ia06baedf64ff41cc7be78750d4dd4543b8ff50d2
2 files changed