After D13283 we were seeing no less than two fatals because apparently something is iterating over something that extends Phobject without implementing its own methods. The culprits are these:
```
1 exception 'DomainException' with message 'Attempting to iterate an object (of class PhabricatorWorkerArchiveTaskQuery) which is not iterable.' in /usr/lib/libphutil/src/object/Phobject.php:50
2 Stack trace:
3 #0 /usr/lib/libphutil/src/object/Phobject.php(42): Phobject->throwOnAttemptedIteration()
4 #1 /usr/lib/phabricator/src/infrastructure/daemon/workers/PhabricatorWorker.php(204): Phobject->rewind()
5 #2 /usr/lib/phabricator/src/applications/drydock/storage/DrydockLease.php(157): PhabricatorWorker::waitForTasks(Array)
6 #3 /usr/lib/phabricator/src/applications/drydock/storage/DrydockLease.php(198): DrydockLease::waitForLeases(Array)
7 #4 /usr/lib/phabricator/src/applications/harbormaster/step/HarbormasterLeaseHostBuildStepImplementation.php(32): DrydockLease->waitUntilActive()
8 #5 /usr/lib/phabricator/src/applications/harbormaster/worker/HarbormasterTargetWorker.php(52): HarbormasterLeaseHostBuildStepImplementation->execute(Object(HarbormasterBuild), Object(HarbormasterBuildTarget))
9 #6 /usr/lib/phabricator/src/infrastructure/daemon/workers/PhabricatorWorker.php(91): HarbormasterTargetWorker->doWork()
10 #7 /usr/lib/phabricator/src/infrastructure/daemon/workers/storage/PhabricatorWorkerActiveTask.php(162): PhabricatorWorker->executeTask()
11 #8 /usr/lib/phabricator/src/infrastructure/daemon/workers/PhabricatorTaskmasterDaemon.php(22): PhabricatorWorkerActiveTask->executeTask()
12 #9 /usr/lib/libphutil/src/daemon/PhutilDaemon.php(183): PhabricatorTaskmasterDaemon->run()
13 #10 /usr/lib/libphutil/scripts/daemon/exec/exec_daemon.php(125): PhutilDaemon->execute()
14 #11 {main}
```
And also:
```lang=diff
-abstract class DrydockConstants extends Phobject {}
+abstract class DrydockConstants {}
```
I removed the extends and it started working again.