* fix bug #317.
* add counter for current task. If it's bigger then zero, do not quit background thread
* Revert "fix issue #317 (#331)"
This reverts commit fc43876cc5.
* fix bug #317.
* add counter for current task. If it's bigger then zero, do not quit background thread
* Revert "fix issue #317 (#331)"
This reverts commit fc43876cc5.