Description of problem:
We recently upgraded from CloudForms 3.2 to 4.2. In the log files, we see error messages like these:

[----] E, [2017-02-06T14:31:22.158779 #23242:633134] ERROR -- : MIQ(MiqPriorityWorker::Runner) ID [99000000062958] PID [23242] GUID [fa486800-ecbb-11e6-b4e7-00505693b910] An
 error has occurred during work processing: undefined method `id' for nil:NilClass
/var/www/miq/vmdb/app/models/miq_queue.rb:469:in `format_full_log_msg'
/var/www/miq/vmdb/app/models/miq_queue.rb:184:in `get'
/var/www/miq/vmdb/app/models/miq_queue_worker_base/runner.rb:74:in `block in get_message_via_sql'
/var/www/miq/vmdb/app/models/miq_queue_worker_base/runner.rb:73:in `loop'
/var/www/miq/vmdb/app/models/miq_queue_worker_base/runner.rb:73:in `get_message_via_sql'
/var/www/miq/vmdb/app/models/miq_queue_worker_base/runner.rb:89:in `get_message'
/var/www/miq/vmdb/app/models/miq_queue_worker_base/runner.rb:150:in `block in do_work'
/var/www/miq/vmdb/app/models/miq_queue_worker_base/runner.rb:146:in `loop'
/var/www/miq/vmdb/app/models/miq_queue_worker_base/runner.rb:146:in `do_work'

Version-Release number of selected component (if applicable):
5.7.0.17

How reproducible:


Steps to Reproduce:
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Actual results:


Expected results:


Additional info: