Implement dynamic and void as types exported by core library.

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

 // Copyright (c) 2016, 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 fasta.library_builder;
 
 import '../combinator.dart' show Combinator;
 
 import '../errors.dart' show InputError, internalError, printUnexpected;
 
 import '../export.dart' show Export;
 
 import '../loader.dart' show Loader;
 
 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;
 
 abstract class LibraryBuilder<T extends TypeBuilder, R> extends Builder {
   final List<Export> exporters = <Export>[];
 
   final List<InputError> compileTimeErrors = <InputError>[];
 
   LibraryBuilder partOfLibrary;
 
@@ skipping 81 matching lines @@
         }
       } else if (constructor.isFactory) {
         return constructor;
       }
     }
     throw internalError("Internal error: No constructor named"
         " '$className::$constructorName' in '$uri'.");
   }
 
   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);
+  }
 }