ZoneSpecification constructor Null safety

const ZoneSpecification(
  1. {HandleUncaughtErrorHandler? handleUncaughtError,
  2. R run(
    1. Zone self,
    2. ZoneDelegate parent,
    3. Zone zone,
    4. R f(
        )
      ),
    5. R runUnary(
      1. Zone self,
      2. ZoneDelegate parent,
      3. Zone zone,
      4. R f(
        1. T arg
        ),
      5. T arg
      ),
    6. R runBinary(
      1. Zone self,
      2. ZoneDelegate parent,
      3. Zone zone,
      4. R f(
        1. T1 arg1,
        2. T2 arg2
        ),
      5. T1 arg1,
      6. T2 arg2
      ),
    7. ZoneCallback<R> registerCallback(
      1. Zone self,
      2. ZoneDelegate parent,
      3. Zone zone,
      4. R f(
          )
        ),
      5. ZoneUnaryCallback<R, T> registerUnaryCallback(
        1. Zone self,
        2. ZoneDelegate parent,
        3. Zone zone,
        4. R f(
          1. T arg
          )
        ),
      6. ZoneBinaryCallback<R, T1, T2> registerBinaryCallback(
        1. Zone self,
        2. ZoneDelegate parent,
        3. Zone zone,
        4. R f(
          1. T1 arg1,
          2. T2 arg2
          )
        ),
      7. ErrorCallbackHandler? errorCallback,
      8. ScheduleMicrotaskHandler? scheduleMicrotask,
      9. CreateTimerHandler? createTimer,
      10. CreatePeriodicTimerHandler? createPeriodicTimer,
      11. PrintHandler? print,
      12. ForkHandler? fork}
      )

      Creates a specification with the provided handlers.

      If the handleUncaughtError is provided, the new zone will be a new "error zone" which will prevent errors from flowing into other error zones (see errorZone, sameErrorZone).

      Implementation

      const factory ZoneSpecification(
          {HandleUncaughtErrorHandler? handleUncaughtError,
          RunHandler? run,
          RunUnaryHandler? runUnary,
          RunBinaryHandler? runBinary,
          RegisterCallbackHandler? registerCallback,
          RegisterUnaryCallbackHandler? registerUnaryCallback,
          RegisterBinaryCallbackHandler? registerBinaryCallback,
          ErrorCallbackHandler? errorCallback,
          ScheduleMicrotaskHandler? scheduleMicrotask,
          CreateTimerHandler? createTimer,
          CreatePeriodicTimerHandler? createPeriodicTimer,
          PrintHandler? print,
          ForkHandler? fork}) = _ZoneSpecification;