Fasta builders.

pkg/fasta/lib/src/builder/dynamic_type_builder.dart

Index: pkg/fasta/lib/src/builder/dynamic_type_builder.dart
diff --git a/pkg/fasta/lib/src/builder/dynamic_type_builder.dart b/pkg/fasta/lib/src/builder/dynamic_type_builder.dart
new file mode 100644
index 0000000000000000000000000000000000000000..47c88901aa8498c6877000fcbf61af6c5ca9cea4
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+++ b/pkg/fasta/lib/src/builder/dynamic_type_builder.dart
@@ -0,0 +1,22 @@
+// 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 fasta.dynamic_type_builder;
+
+import 'builder.dart' show
+    TypeBuilder,
+    TypeDeclarationBuilder;
+
+// TODO(ahe): Make const class.
+class DynamicTypeBuilder<T extends TypeBuilder, R>
+    extends TypeDeclarationBuilder<T, R> {
+  final R type;
+
+  DynamicTypeBuilder(this.type)
+      : super (null, 0, "dynamic", null, null);
+
+  R buildType(List<T> arguments) => type;
+
+  R buildTypesWithBuiltArguments(List<R> arguments) => type;
+}