Remove DirectoryException and LinkException from dart:io and use FileException instaed.

sdk/lib/_internal/dartdoc/lib/src/export_map.dart

 // Copyright (c) 2013, 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.
 
 /// This library uses the Dart analyzer to find the exports for a set of
 /// libraries. It stores these exports in an [ExportMap]. This is used to
 /// display exported members as part of the exporting library, since dart2js
 /// doesn't provide this information itself.
 library export_map;
 
@@ skipping 28 matching lines @@
   /// `import` or `export`.
   factory ExportMap.parse(Iterable<Uri> libraries, String packageRoot) {
     var exports = <String, List<Export>>{};
 
     void traverse(String path) {
       if (exports.containsKey(path)) return;
 
       var importsAndExports;
       try {
         importsAndExports = _importsAndExportsForFile(path, packageRoot);
-      } on FileException catch (_) {
+      } on FileSystemException catch (_) {
         // Ignore unreadable/nonexistent files.
         return;
       }
 
       var exportsForLibrary = <String, Export>{};
       for (var export in importsAndExports.last) {
         addOrMergeExport(exportsForLibrary, export.path, export);
       }
       exports[path] = new List.from(exportsForLibrary.values);
       exports[path].map((directive) => directive.path).forEach(traverse);
@@ skipping 229 matching lines @@
 /// A simple visitor that collects import and export nodes.
 class _ImportExportCollector extends GeneralizingASTVisitor {
   final imports = <ImportDirective>[];
   final exports = <ExportDirective>[];
 
   _ImportExportCollector();
 
   visitImportDirective(ImportDirective node) => imports.add(node);
   visitExportDirective(ExportDirective node) => exports.add(node);
 }