Fixes for review comments.

pkg/front_end/lib/src/incremental/file_state.dart

 // Copyright (c) 2017, 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.
 
 import 'dart:async';
 import 'dart:typed_data';
 
 import 'package:crypto/crypto.dart';
 import 'package:front_end/file_system.dart';
 import 'package:front_end/src/dependency_walker.dart' as graph;
@@ skipping 117 matching lines @@
     _exportedLibraries = <FileState>[];
     _partFiles = <FileState>[];
     _exports = <NamespaceExport>[];
     {
       FileState coreFile = await _getFileForRelativeUri('dart:core');
       // TODO(scheglov) add error handling
       if (coreFile != null) {
         _importedLibraries.add(coreFile);
       }
     }
-    for (ImportDirective import_ in listener.imports) {
+    for (NamespaceDirective import_ in listener.imports) {
       FileState file = await _getFileForRelativeUri(import_.uri);
       if (file != null) {
         _importedLibraries.add(file);
       }
     }
     await _addVmTargetImportsForCore();
-    for (ExportDirective export_ in listener.exports) {
+    for (NamespaceDirective export_ in listener.exports) {
       FileState file = await _getFileForRelativeUri(export_.uri);
       if (file != null) {
         _exportedLibraries.add(file);
         _exports.add(new NamespaceExport(file, export_.combinators));
       }
     }
     for (String uri in listener.parts) {
       FileState file = await _getFileForRelativeUri(uri);
       if (file != null) {
         _partFiles.add(file);
@@ skipping 124 matching lines @@
 }
 
 /// Information about a single `export` directive.
 class NamespaceExport {
   final FileState library;
   final List<NamespaceCombinator> combinators;
 
   NamespaceExport(this.library, this.combinators);
 
   /// Return `true` if the [name] satisfies the sequence of the [combinators].
-  bool filter(String name) {
+  bool isExposed(String name) {
     for (NamespaceCombinator combinator in combinators) {
       if (combinator.isShow) {
         if (!combinator.names.contains(name)) {
           return false;
         }
       } else {
         if (combinator.names.contains(name)) {
           return false;
         }
       }
@@ skipping 91 matching lines @@
       node.isEvaluated = true;
       cycle.libraries.add(node.file);
     }
     topologicallySortedCycles.add(cycle);
   }
 
   _LibraryNode getNode(FileState file) {
     return nodesOfFiles.putIfAbsent(file, () => new _LibraryNode(this, file));
   }
 }