Implement modular compilation

test/codegen/dir/html_input_a.dart

Index: test/codegen/dir/html_input_a.dart
diff --git a/test/codegen/dir/html_input_a.dart b/test/codegen/dir/html_input_a.dart
deleted file mode 100644
index e38a5d76c063c1fe2593ec2cddd044c79f081c5a..0000000000000000000000000000000000000000
--- a/test/codegen/dir/html_input_a.dart
+++ /dev/null
@@ -1,11 +0,0 @@
-// Copyright (c) 2015, 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.
-
-import 'html_input_b.dart';
-import 'html_input_c.dart';
-
-main() {
-  print('fib(${x} + ${y}) = ');
-  print('  ... ${fib(x + y)}');
-}