getCpuSamples method Null safety
override
    The getCpuSamples RPC is used to retrieve samples collected by the CPU
profiler. Only samples collected in the time range [timeOriginMicros, timeOriginMicros + timeExtentMicros] will be reported.
If the profiler is disabled, an RPC error response will be returned.
If isolateId refers to an isolate which has exited, then the Collected
Sentinel is returned.
See CpuSamples.
This method will throw a SentinelException in the case a Sentinel is returned.
Implementation
@override
Future<CpuSamples> getCpuSamples(
        String isolateId, int timeOriginMicros, int timeExtentMicros) =>
    _call('getCpuSamples', {
      'isolateId': isolateId,
      'timeOriginMicros': timeOriginMicros,
      'timeExtentMicros': timeExtentMicros
    });