Allow Platform.executable for JIT app snapshots.

tests/standalone/io/https_unauthorized_test.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.
 //
 // OtherResources=certificates/server_chain.pem
 // OtherResources=certificates/server_key.pem
+// OtherResources=certificates/untrusted_server_chain.pem
+// OtherResources=certificates/untrusted_server_key.pem
+// OtherResources=certificates/trusted_certs.pem
+// OtherResources=https_unauthorized_client.dart
 
 // This test verifies that secure connections that fail due to
 // unauthenticated certificates throw exceptions in HttpClient.
 
 import "package:expect/expect.dart";
 import "package:path/path.dart";
 import "dart:async";
 import "dart:io";
 
 const HOST_NAME = "localhost";
@@ skipping 14 matching lines @@
       HOST_NAME, 0, untrustedServerContext, backlog: 5)
   .then((server) {
     server.listen((HttpRequest request) {
       request.listen((_) { }, onDone: () { request.response.close(); });
     }, onError: (e) { if (e is! HandshakeException) throw e; });
     return server;
   });
 }
 
 void main() {
-  var clientScript = Platform.script
-                             .resolve('https_unauthorized_client.dart')
-                             .toFilePath();
+  var clientScript = localFile('https_unauthorized_client.dart');
   Future clientProcess(int port) {
     return Process.run(Platform.executable,
         [clientScript, port.toString()])
     .then((ProcessResult result) {
       if (result.exitCode != 0 || !result.stdout.contains('SUCCESS')) {
         print("Client failed");
         print("  stdout:");
         print(result.stdout);
         print("  stderr:");
         print(result.stderr);
         Expect.fail('Client subprocess exit code: ${result.exitCode}');
       }
     });
   }
 
   runServer().then((server) {
     clientProcess(server.port).then((_) {
       server.close();
     });
   });
 }