Use dart2js_plaform.dill from the sdk.

pkg/compiler/lib/src/kernel/kernel_strategy.dart

 // Copyright (c) 2017, 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.
 
 library dart2js.kernel.frontend_strategy;
 
 import '../../compiler_new.dart' as api;
 import '../common.dart';
 import '../common_elements.dart';
 import '../common/backend_api.dart';
@@ skipping 45 matching lines @@
       ResolvedUriTranslator uriTranslator,
       ScriptLoader scriptLoader,
       api.CompilerInput compilerInput,
       ElementScanner scriptScanner,
       LibraryDeserializer deserializer,
       PatchResolverFunction patchResolverFunc,
       PatchParserTask patchParser,
       env.Environment environment,
       DiagnosticReporter reporter,
       Measurer measurer) {
-    return new KernelLibraryLoaderTask(
+    return new KernelLibraryLoaderTask(_options.platformConfigUri.resolve("."),
         _elementMap, compilerInput, reporter, measurer);
   }
 
   @override
   ElementEnvironment get elementEnvironment => _elementMap.elementEnvironment;
 
   @override
   CommonElements get commonElements => _elementMap.commonElements;
 
   DartTypes get dartTypes => _elementMap.types;
@@ skipping 151 matching lines @@
   int get preMirrorsMethodCount {
     // TODO(redemption): Implement this.
     return null;
   }
 
   @override
   void onQueueEmpty(Enqueuer enqueuer, Iterable<ClassEntity> recentClasses) {
     // TODO(redemption): Implement this.
   }
 }