- Using `%`-formatting in all `logging.log()` calls (e.g. `info()`).
  I am not opposed to using `.format()` but `logging` "prefers"
  `%`-formatting (and I wanted to be consistent because hobgoblins).
- Adding non-public globals for helper thread names, this was
  especially needed because I accidentally broke this in googleapis#4476 when
  I changed `consume bidirectional stream` to `ConsumeBidirectionalStream`
  in one place, not two.
- Adding docstring to `QueueCallbackThread` that explains what it
  does (I'll refactor this class in a follow-up)
- Adding a logging statement when a `QueueCallbackThread` exits
- Changing indents / using much more vertical space in calls to
  `request_queue.put()` in `subscriber.message.Message`. (I came across
  these when trying to understand how `QueueCallbackThread` interacts
  with `Policy.on_callback_request`)
- Logging an exit statement when `maintain_leases` exits
- Changing `GPRC` to `gRPC` in a docstring
- Moving "Creating callback requests thread (not starting)." until
  right before the resource is created
- Changing "Spawning" to "Starting" in a log message to match others

- Using `%`-formatting in all `logging.log()` calls (e.g. `info()`).
  I am not opposed to using `.format()` but `logging` "prefers"
  `%`-formatting (and I wanted to be consistent because hobgoblins).
- Adding non-public globals for helper thread names, this was
  especially needed because I accidentally broke this in #4476 when
  I changed `callback requests worker` to `CallbackRequestsWorker`
  in one place, not two.
- Adding docstring to `QueueCallbackThread` that explains what it
  does (I'll refactor this class in a follow-up)
- Adding a logging statement when a `QueueCallbackThread` exits
- Changing indents / using much more vertical space in calls to
  `request_queue.put()` in `subscriber.message.Message`. (I came across
  these when trying to understand how `QueueCallbackThread` interacts
  with `Policy.on_callback_request`)
- Changing `GPRC` to `gRPC` in a docstring
- Moving "Creating callback requests thread (not starting)." until
  right before the resource is created
- Changing "Spawning" to "Starting" in a log message to match others

- Using `%`-formatting in all `logging.log()` calls (e.g. `info()`).
  I am not opposed to using `.format()` but `logging` "prefers"
  `%`-formatting (and I wanted to be consistent because hobgoblins).
- Adding non-public globals for helper thread names, this was
  especially needed because I accidentally broke this in #4476 when
  I changed `callback requests worker` to `CallbackRequestsWorker`
  in one place, not two.
- Adding docstring to `QueueCallbackThread` that explains what it
  does (I'll refactor this class in a follow-up)
- Adding a logging statement when a `QueueCallbackThread` exits
- Changing indents / using much more vertical space in calls to
  `request_queue.put()` in `subscriber.message.Message`. (I came across
  these when trying to understand how `QueueCallbackThread` interacts
  with `Policy.on_callback_request`)
- Changing `GPRC` to `gRPC` in a docstring
- Moving "Creating callback requests thread (not starting)." until
  right before the resource is created
- Changing "Spawning" to "Starting" in a log message to match others