Update charted to 0.4.8 and roll

packages/web_components/lib/build/html_import_annotation_recorder.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 library web_components.build.html_import_recorder_inliner;
 
-import 'package:analyzer/src/generated/element.dart';
+import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/type.dart';
 import 'package:initialize/transformer.dart';
 import 'package:path/path.dart' as path;
 import '../src/normalize_path.dart';
 
 /// [InitializerPlugin] for @HtmlImport annotations. This records all paths
 /// seen, normalizes them relative to the entry point, and records the values in
 /// [importPaths].
 ///
 /// Note: This does nothing with the paths on its own, a separate step needs to
 /// add the imports to the entry point document.
@@ skipping 75 matching lines @@
       return null;
     }
 
     importPaths
         .add(normalizeHtmlImportPath(originalImportPath, package, libPath));
 
     // Don't emit an InitEntry.
     return null;
   }
 }