Use FileSystem to read files in SourceLoader and TranslateUri.

pkg/compiler/lib/src/kernel/fasta_support.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.
 
 /// Additions to Fasta for generating .dill (Kernel IR) files with dart2js patch
 /// files and native hooks.
 library compiler.src.kernel.fasta_support;
 
 // TODO(sigmund): get rid of this file. Fasta should be agnostic of the
 // target platform, at which point this should not be necessary. In particular,
 // we need to:
 //  - add a fasta flag to configure the platform library location.
 //  - add a fasta flag to specify which sdk libraries should be built-in
 //    (that would replace `loadExtraRequiredLibraries`).
 //  - add flags to fasta to turn on various transformations.
 //  - get rid of `native` in dart2js patches or unify the syntax with the VM.
 
 import 'dart:async' show Future;
 import 'dart:io' show exitCode;
 
+import 'package:front_end/physical_file_system.dart';
 import 'package:kernel/ast.dart' show Source;
 
 import 'package:front_end/src/fasta/compiler_context.dart' show CompilerContext;
 import 'package:front_end/src/fasta/dill/dill_target.dart' show DillTarget;
 import 'package:front_end/src/fasta/fasta.dart' show CompileTask;
 import 'package:front_end/src/fasta/kernel/kernel_target.dart'
     show KernelTarget;
 import 'package:front_end/src/fasta/loader.dart' show Loader;
 import 'package:front_end/src/fasta/parser/parser.dart' show optional;
 import 'package:front_end/src/fasta/scanner/token.dart' show Token;
 import 'package:front_end/src/fasta/ticker.dart' show Ticker;
 import 'package:front_end/src/fasta/translate_uri.dart' show TranslateUri;
 
 /// Generates a platform.dill file containing the compiled Kernel IR of the
 /// dart2js SDK.
 Future compilePlatform(Uri patchedSdk, Uri output, {Uri packages}) async {
   Uri deps = Uri.base.resolveUri(new Uri.file("${output.toFilePath()}.d"));
-  TranslateUri uriTranslator = await TranslateUri.parse(patchedSdk, packages);
+  TranslateUri uriTranslator = await TranslateUri.parse(
+      PhysicalFileSystem.instance, patchedSdk, packages);
   var ticker = new Ticker(isVerbose: false);
   var dillTarget = new DillTargetForDart2js(ticker, uriTranslator);
   var kernelTarget =
       new KernelTargetForDart2js(dillTarget, uriTranslator, false);
 
   kernelTarget.read(Uri.parse("dart:core"));
   await dillTarget.writeOutline(null);
   await kernelTarget.writeOutline(output);
 
   if (exitCode != 0) return null;
@@ skipping 19 matching lines @@
   }
 }
 
 /// Specializes [KernelTarget] to build kernel for dart2js: no transformations
 /// are run, JS-specific libraries are included in the SDK, and native clauses
 /// have no string parameter.
 class KernelTargetForDart2js extends KernelTarget {
   KernelTargetForDart2js(
       DillTarget target, TranslateUri uriTranslator, bool strongMode,
       [Map<String, Source> uriToSource])
-      : super(target, uriTranslator, strongMode, uriToSource);
+      : super(PhysicalFileSystem.instance, target, uriTranslator, strongMode,
+            uriToSource);
 
   @override
   Token skipNativeClause(Token token) => _skipNative(token);
 
   @override
   String extractNativeMethodName(Token token) => null;
 
   @override
   void loadExtraRequiredLibraries(Loader loader) => _loadExtras(loader);
 
@@ skipping 50 matching lines @@
   'dart:_native_typed_data',
   'dart:_internal',
   'dart:_js_helper',
   'dart:_interceptors',
   'dart:_foreign_helper',
   'dart:_js_mirrors',
   'dart:_js_names',
   'dart:_js_embedded_names',
   'dart:_isolate_helper',
 ];