Fix node manager failure when ClientTable has a  disconnected entry. (#2905)
Fix node manager failure when ClientTable has a  disconnected entry. (#2905)

When a new raylet starts, `ClientAdded` will be called with the disconnected client data. However, since the client was closed, the connection will fail.
stephanie-wang/ray,richardliaw/ray,pcmoritz/ray-1,robertnishihara/ray,stephanie-wang/ray,richardliaw/ray,pcmoritz/ray-1,robertnishihara/ray,ray-project/ray,ujvl/ray-ng,ujvl/ray-ng,ray-project/ray,ray-project/ray,ujvl/ray-ng,robertnishihara/ray,atumanov/ray,richardliaw/ray,stephanie-wang/ray,richardliaw/ray,ray-project/ray,stephanie-wang/ray,stephanie-wang/ray,pcmoritz/ray-1,robertnishihara/ray,ray-project/ray,ujvl/ray-ng,richardliaw/ray,robertnishihara/ray,atumanov/ray,atumanov/ray,stephanie-wang/ray,atumanov/ray,pcmoritz/ray-1,richardliaw/ray,pcmoritz/ray-1,richardliaw/ray,pcmoritz/ray-1,pcmoritz/ray-1,robertnishihara/ray,stephanie-wang/ray,ray-project/ray,robertnishihara/ray,atumanov/ray,pcmoritz/ray-1,robertnishihara/ray,atumanov/ray,ray-project/ray,atumanov/ray,ray-project/ray,atumanov/ray,stephanie-wang/ray,stephanie-wang/ray,richardliaw/ray,robertnishihara/ray