anchor.diff:        ];
         _recalculateInstantEventTimes();
       }
  -    return _instantEvents;
  -  }
  -
  -  List<HttpInstantEvent> _instantEvents;
  +    return _instantEvents!;
  +  }
  +
  +  List<HttpInstantEvent>? _instantEvents;
   
     /// A list of all cookies contained within the request headers.
     @override
  
positive.code:   final TraceEvent _event;
  
    @override
    String get name => _event.name;
  
    /// The time the instant event was recorded.
    @override
    int get timestampMicros => _event.timestampMicros;
  }
  
  class DartIOHttpInstantEvent extends HttpInstantEvent {
  
negative.code:       // (phases 'b' and 'e')?
        if (traceEvent.phase == TraceEvent.asyncInstantPhase &&
            traceEvent.name == 'Response body') {
          encodedData.addAll((traceEvent.args!['data'] as List).cast<int>());
        }
      }
  
  