Add package config support to dart:isolate

runtime/bin/platform_patch.dart

 // 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.
 
 patch class _Platform {
   /* patch */ static int _numberOfProcessors()
       native "Platform_NumberOfProcessors";
-  /* patch */ static String _pathSeparator() native "Platform_PathSeparator";
+  /* patch */ static String _pathSeparator()
+      native "Platform_PathSeparator";
   /* patch */ static String _operatingSystem()
       native "Platform_OperatingSystem";
-  /* patch */ static _localHostname() native "Platform_LocalHostname";
-  /* patch */ static _executable() native "Platform_ExecutableName";
+  /* patch */ static _localHostname()
+      native "Platform_LocalHostname";
+  /* patch */ static _executable()
+      native "Platform_ExecutableName";
   /* patch */ static _resolvedExecutable()
       native "Platform_ResolvedExecutableName";
-  /* patch */ static _environment() native "Platform_Environment";
+  /* patch */ static _environment()
+      native "Platform_Environment";
   /* patch */ static List<String> _executableArguments()
-       native "Platform_ExecutableArguments";
-  /* patch */ static String _packageRoot() => VMLibraryHooks.packageRoot;
-  /* patch */ static String _packageConfig() => VMLibraryHooks.packageConfig;
-  /* patch */ static String _version() native "Platform_GetVersion";
+      native "Platform_ExecutableArguments";
+  /* patch */ static String _version()
+      native "Platform_GetVersion";
+
+  /* patch */ static String _packageRoot()
+      => VMLibraryHooks.packageRootString;
+  /* patch */ static String _packageConfig()
+      => VMLibraryHooks.packageConfigString;
 }