Merge "GD Reactor: Fix a potential use-after-free"

        reactable->on_write_ready_.Run();

      }

      {

        std::lock_guard<std::mutex> reactable_lock(reactable->mutex_);

        std::unique_lock<std::mutex> reactable_lock(reactable->mutex_);

        reactable->is_executing_ = false;

        if (reactable->removed_) {

          reactable->finished_promise_->set_value();

          reactable_lock.unlock();

          delete reactable;

        }

      }