Observer: log when we drop an event.
Observer: log when we drop an event.

This is a potential deadlock situation. In case a system blocks, it'd be
good to have logs about this event so it will be easier to debug.

manifoldco/torus-cli,manifoldco/torus-cli,luizbranco/torus-cli,manifoldco/torus-cli,luizbranco/torus-cli,luizbranco/torus-cli