anchor.diff:        _setGistDescription(gist.description);
         _setGistId(gist.id);
   
  -      GistFile dart = chooseGistFile(gist, ['main.dart'], (f) => f.endsWith('.dart'));
  +      GistFile dart =
  +          chooseGistFile(gist, ['main.dart'], (f) => f.endsWith('.dart'));
         GistFile html = chooseGistFile(gist, ['index.html', 'body.html']);
         GistFile css = chooseGistFile(gist, ['styles.css', 'style.css']);
   
  
positive.code:     _runProgress.hidden(false);
  
      var input = new CompileRequest()..source = context.dartSource;
      dartServices.compile(input).timeout(longServiceCallTimeout).then(
          (CompileResponse response) {
        _clearOutput();
        return executionService.execute(
            _context.htmlSource, _context.cssSource, response.result);
  
negative.code: 
        _displayIssues(result.issues);
  
        _context.dartDocument.setAnnotations(result.issues
            .map((AnalysisIssue issue) {
          int startLine = lines.getLineForOffset(issue.charStart);
          int endLine =
              lines.getLineForOffset(issue.charStart + issue.charLength);
  
          Position start = new Position(
              startLine, issue.charStart - lines.offsetForLine(startLine));
          Position end = new Position(endLine, issue.charStart +
              issue.charLength -
              lines.offsetForLine(startLine));
  
          return new Annotation(issue.kind, issue.message, issue.line,
              start: start, end: end);
  