Got this debugging another error. Filing here for reference. Original code: https://phabricator.intern.facebook.com/P59317705
if (__DEV__) {
            if (!isErrorRecovery && fiber.tag === ClassComponent) {
              warnAboutUpdateOnUnmounted(fiber);
            }
          }
          return;
        }
      }
      node = node.return;
    }
  }
  function recalculateCurrentTime(): ExpirationTime {
    
    mostRecentCurrentTimeMs = now() - originalStartTimeMs;
    mostRecentCurrentTime = msToExpirationTime(mostRecentCurrentTimeMs);
    return mostRecentCurrentTime;
  }
  function deferredUpdates<A>(fn: () => A): A {
    const previousExpirationContext = expirationContext;
    const currentTime = recalculateCurrentTime();
    expirationContext = computeAsyncExpiration(currentTime);
    try {
      return fn();
    } finally {
      expirationContext = previousExpirationContext;
    }
  }
  function syncUpdates<A, B, C0, D, R>(
    fn: (A, B, C0, D) => R,
    a: A,