* ensure all uv handles are closed before ending worker's loop
* add DCHECK to test that the Worker loop is finished
* don't call deprecated uv_loop_new(), uv_loop_delete()
* make cpplint happy
* fix comment error
* empty commit for CI
* tweak DCHECK expression
* extract-method: stop_and_close_uv_loop()
* fix DCHECK oops
435c9c1486