Fix running standalone-precompiled when passing a package-root/-file/-map.

runtime/bin/main.cc

 // Copyright (c) 2012, 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.
 
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 
 #include "include/dart_api.h"
 #include "include/dart_tools_api.h"
@@ skipping 1231 matching lines @@
       }
     }
 
     if (has_noopt || has_gen_precompiled_snapshot) {
       Dart_QualifiedFunctionName standalone_entry_points[] = {
         { "dart:_builtin", "::", "_getMainClosure" },
         { "dart:_builtin", "::", "_getPrintClosure" },
         { "dart:_builtin", "::", "_getUriBaseClosure" },
         { "dart:_builtin", "::", "_resolveUri" },
         { "dart:_builtin", "::", "_setWorkingDirectory" },
+        { "dart:_builtin", "::", "_setPackageRoot" },
+        { "dart:_builtin", "::", "_addPackageMapEntry" },
+        { "dart:_builtin", "::", "_loadPackagesMap" },
         { "dart:_builtin", "::", "_loadDataAsync" },
         { "dart:io", "::", "_makeUint8ListView" },
         { "dart:io", "::", "_makeDatagram" },
         { "dart:io", "::", "_setupHooks" },
         { "dart:io", "::", "_getWatchSignalInternal" },
         { "dart:io", "CertificateException", "CertificateException." },
         { "dart:io", "HandshakeException", "HandshakeException." },
         { "dart:io", "OSError", "OSError." },
         { "dart:io", "TlsException", "TlsException." },
         { "dart:io", "X509Certificate", "X509Certificate._" },
@@ skipping 257 matching lines @@
   Platform::Exit(Process::GlobalExitCode());
 }
 
 }  // namespace bin
 }  // namespace dart
 
 int main(int argc, char** argv) {
   dart::bin::main(argc, argv);
   UNREACHABLE();
 }