Change dart:io Platform.script to return a Uri.

sdk/lib/_internal/compiler/samples/jsonify/jsonify.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.
 
 import 'dart:io';
 import 'dart:convert';
 
 // TODO(ahe): Should be dart:mirrors.
 import '../../implementation/mirrors/mirrors.dart';
 
@@ skipping 23 matching lines @@
 
 main(List<String> arguments) {
   handler = new FormattingDiagnosticHandler()
       ..throwOnError = true;
 
   outputUri =
       handler.provider.cwd.resolve(nativeToUriPath(arguments.first));
   output = new File(arguments.first).openSync(mode: FileMode.WRITE);
 
   Uri myLocation =
-      handler.provider.cwd.resolve(nativeToUriPath(Platform.script));
+      handler.provider.cwd.resolveUri(Platform.script);
 
   sdkRoot = myLocation.resolve(SDK_ROOT).resolve('../');
 
   // Get the names of public dart2js libraries.
   Iterable<String> names = LIBRARIES.keys.where(isPublicDart2jsLibrary);
 
   // Turn the names into uris by prepending dart: to them.
   List<Uri> uris = names.map((String name) => Uri.parse('dart:$name')).toList();
 
   analyze(uris, myLocation.resolve(SDK_ROOT), null, handler.provider, handler)
@@ skipping 30 matching lines @@
 // DO NOT EDIT.
 // This file is generated by jsonify.dart.
 
 library dart.sdk_sources;
 
 const Map<String, String> SDK_SOURCES = const <String, String>''');
   output.writeStringSync(JSON.encode(map).replaceAll(r'$', r'\$'));
   output.writeStringSync(';\n');
   output.closeSync();
 }