anchor.diff:    }
   
     void _handleStdoutEvent(Event event) {
  -    final String text = decodeBase64(event.bytes);
  +    final String text = decodeBase64(event.bytes!);
       appendStdio(text);
     }
   
     void _handleStderrEvent(Event event) {
  -    final String text = decodeBase64(event.bytes);
  +    final String text = decodeBase64(event.bytes!);
       // TODO(devoncarew): Change to reporting stdio along with information about
       // whether the event was stdout or stderr.
       appendStdio(text);
  
positive.code: /// VM and events emitted from other UI.
  class ConsoleService extends Disposer {
    void appendInstanceRef({
      String name,
      @required InstanceRef value,
      @required RemoteDiagnosticsNode diagnostic,
      @required IsolateRef isolateRef,
      bool forceScrollIntoView = false,
      bool expandAll = false,
    }) async {
  
negative.code:   void _handleExtensionEvent(Event e) async {
      if (e.extensionKind == 'Flutter.Error' ||
          e.extensionKind == 'Flutter.Print') {
        if (serviceManager.connectedApp.isProfileBuildNow != true) {
          // The app isn't a debug build.
          return;
        }
        // TODO(jacobr): events may be out of order. Use unique ids to ensure
        // consistent order of regular print statements and structured messages.
        appendInstanceRef(
          value: null,
          diagnostic: RemoteDiagnosticsNode(
            e.extensionData!.data,
            objectGroup,
            false,
            null,
          ),
          isolateRef: objectGroup!.inspectorService.isolateRef,
          expandAll: true,
        );
      }
  