anchor.diff:  
           final wasSelected = extensionState.isSelected;
   
  -        serviceManager.serviceExtensionManager!.setServiceExtensionState(
  +        serviceManager.serviceExtensionManager.setServiceExtensionState(
             extensionState.description.extension,
             enabled: !wasSelected,
             value: wasSelected
  
positive.code:     _extensionStates = List.filled(widget.extensions.length, false);
      for (int i = 0; i < widget.extensions.length; i++) {
        final extension = widget.extensions[i];
        final state = serviceManager.serviceExtensionManager!
            .getServiceExtensionState(extension.extension);
        _extensionStates[i] = state.value.enabled;
        // Listen for extension state changes so that we can update the value of
  
negative.code:         });
        });
        // Track whether the extension is actually exposed by the VM.
        final listenable = serviceManager.serviceExtensionManager
            .hasServiceExtension(extensionName);
        extension.isAvailable = listenable.value;
        addAutoDisposeListener(
  