common.decode, common.decode-stress, and client.cleancall tests silently die after their nth fault on Server2016

decode and decode-stress: output just ends:
```
2020-12-05T20:33:13.7774875Z 12: Testing far call/jmp
2020-12-05T20:33:13.7775258Z 12: Bad instruction, instance 3
```
Similarly for cleancall:
```
2020-12-05T20:34:14.4096097Z in restore_state for our clean call crash 1
2020-12-05T20:34:14.4096607Z Access violation, instance 1
```

Yet decode-bad works, and earlier faults work: so clearly faults in general
are working. Not clear what is happening.