- Add getters for the current packageRoot or packageMap.

runtime/bin/platform_patch.dart

Index: runtime/bin/platform_patch.dart
diff --git a/runtime/bin/platform_patch.dart b/runtime/bin/platform_patch.dart
index c917b54f77c2d65f54543f218e068226859e4e9e..97afd96225023d75a169af9f79ee1597497dc0f3 100644
--- a/runtime/bin/platform_patch.dart
+++ b/runtime/bin/platform_patch.dart
@@ -15,6 +15,21 @@ patch class _Platform {
   /* patch */ static _environment() native "Platform_Environment";
   /* patch */ static List<String> _executableArguments()
        native "Platform_ExecutableArguments";
-  /* patch */ static String _packageRoot() native "Platform_PackageRoot";
   /* patch */ static String _version() native "Platform_GetVersion";
+
+  /* patch */ static Future<Uri> get packageRoot {
+  var hook = VMLibraryHooks.getPackageRoot;
+    if (hook == null) {
+      throw new UnimplementedError("Platform.packageRoot");
+    }
+    return hook();
+  }
+
+  /* patch */ static Future<Map<String, Uri>> get packageMap {
+    var hook = VMLibraryHooks.getPackageMap;
+    if (hook == null) {
+      throw new UnimplementedError("Platform.packageMap");
+    }
+    return hook();
+  }
 }