Task manager stats sending was broken with openstacksdk updates and
fixed in I8617ab2895d1544a6902ae5a3d6a97b87bfd2ec9.
What used to happen is that openstacksdk run_task() would call
post_run_task(); however with changes to use a threadpool this became
an async call so was not reflecting the post-run state but just the
post-insert-into-threadpool-queue state.
The referenced change moved the post_run_task() call into
submit_task(), where it is called after the task has been wait()ed
for (and actually run).
Unfortunatley, since this file overrides submit_task, it means that
post_run_task is not being called any more and we are not producing
timing stats.
I believe we can use the openstacksdk task manager's submit_task
directly. There are two differences; the "raw" argument was removed
from upstream with I7b46e263a76d84573bdfbbece57b1048764ed939 and is no
longer necessary. The ManagerStoppedException is private to this file
and doesn't appear to have an external dependencies; thus the
openstacksdk's TaskManagerStopped exception will work just the same.
Change-Id: I427e6ae9e4beae6d551427fc12a3cde2c1d03aba
d1326df6ee