anchor.diff:  
       buf.writeln('</div>');
     }
  -
  -  void generateNotApplicablePage() {
  -    buf.write('This page is not applicable for this server.');
  -  }
   }
   
   class DiagnosticsSite extends Site implements AbstractGetHandler {
  
positive.code: 
  /// A page with a proscriptive notion of layout.
  abstract class DiagnosticPage extends Page {
    final Site site;
  
    DiagnosticPage(this.site, String id, String title, {String description})
        : super(id, title, description: description);
  
    bool get isNavPage => false;
  
    AbstractAnalysisServer get server =>
        (site as DiagnosticsSite).socketServer.analysisServer;
  
    Future<void> generateContainer(Map<String, String> params) async {
      // TODO(brianwilkerson) Determine whether this await is necessary.
  
negative.code: class NotFoundPage extends DiagnosticPage {
    final String path;
  
    NotFoundPage(DiagnosticsSite site, this.path)
        : super(site, '', '404 Not found', description: "'$path' not found.");
  
    Future generateContent(Map<String, String> params) async {
  