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pkg/front_end/lib/src/fasta/builder/library_builder.dart

Index: pkg/front_end/lib/src/fasta/builder/library_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/builder/library_builder.dart b/pkg/front_end/lib/src/fasta/builder/library_builder.dart
index f4662c1f0bab2d9c98255d3da369286d4b6caa51..e4218332f279ffa0298becb32fe5002e4b7107d0 100644
--- a/pkg/front_end/lib/src/fasta/builder/library_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/library_builder.dart
@@ -16,7 +16,7 @@ import '../messages.dart' show nit, warning;
 
 import '../util/relativize.dart' show relativizeUri;
 
-import 'builder.dart' show Builder, ClassBuilder, TypeBuilder;
+import 'builder.dart' show Builder, DynamicTypeBuilder, ClassBuilder, TypeBuilder, VoidTypeBuilder;
 
 import 'scope.dart' show Scope;
 
@@ -118,4 +118,9 @@ abstract class LibraryBuilder<T extends TypeBuilder, R> extends Builder {
   }
 
   int finishTypeVariables(ClassBuilder object) => 0;
+
+  void becomeCoreLibrary(dynamicType, voidType) {
+    addBuilder("dynamic", new DynamicTypeBuilder<T, dynamic>(dynamicType, this, -1), -1);
+    addBuilder("void", new VoidTypeBuilder<T, dynamic>(voidType, this, -1), -1);
+  }
 }