Compute API signatures of files.

pkg/front_end/lib/src/incremental_kernel_generator_impl.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:io';
 
 import 'package:front_end/file_system.dart';
 import 'package:front_end/incremental_kernel_generator.dart';
 import 'package:front_end/src/base/api_signature.dart';
@@ skipping 41 matching lines @@
   /// The compiler options, such as the [FileSystem], the SDK dill location,
   /// etc.
   final ProcessedOptions _options;
 
   /// The object that knows how to resolve "package:" and "dart:" URIs.
   final TranslateUri _uriTranslator;
 
   /// The logger to report compilation progress.
   final PerformanceLog _logger;
 
-  /// The current file system state.
-  final FileSystemState _fsState;
-
   /// The byte storage to get and put serialized data.
   final ByteStore _byteStore;
 
   /// The URI of the program entry point.
   final Uri _entryPoint;
 
   /// The salt to mix into all hashes used as keys for serialized data.
   List<int> _salt;
 
+  /// The current file system state.
+  FileSystemState _fsState;
+
   /// Latest compilation signatures produced by [computeDelta] for libraries.
   final Map<Uri, String> _latestSignature = {};
 
   /// The set of absolute file URIs that were reported through [invalidate]
   /// and not checked for actual changes yet.
   final Set<Uri> _invalidatedFiles = new Set<Uri>();
 
   IncrementalKernelGeneratorImpl(
       this._options, this._uriTranslator, this._entryPoint)
       : _logger = _options.logger,
-        _fsState = new FileSystemState(_options.fileSystem, _uriTranslator),
         _byteStore = _options.byteStore {
     _computeSalt();
+    _fsState = new FileSystemState(_options.fileSystem, _uriTranslator, _salt);
   }
 
   @override
   Future<DeltaProgram> computeDelta(
       {Future<Null> watch(Uri uri, bool used)}) async {
     return await _logger.runAsync('Compute delta', () async {
       await _refreshInvalidatedFiles();
 
       // Ensure that the graph starting at the entry point is ready.
       FileState entryLibrary =
@@ skipping 229 matching lines @@
   /// TODO(scheglov) Use API signatures.
   /// TODO(scheglov) Or use tree shaking and compute signatures of outlines.
   final String signature;
 
   /// Kernel libraries for libraries in the [cycle].  Bodies of dependencies
   /// are not included, but but references to those dependencies are included.
   final List<Library> kernelLibraries;
 
   _LibraryCycleResult(this.cycle, this.signature, this.kernelLibraries);
 }