Add a draft of traversing visitor which will analyse function.

lib/compiler/implementation/dart_backend/dart_backend.dart

Index: lib/compiler/implementation/dart_backend/dart_backend.dart
diff --git a/lib/dom/templates/dom/native/cpp_derived_sources.template b/lib/compiler/implementation/dart_backend/dart_backend.dart
similarity index 67%
copy from lib/dom/templates/dom/native/cpp_derived_sources.template
copy to lib/compiler/implementation/dart_backend/dart_backend.dart
index c9530e875a085289ffb7a53c61695813b1814a9a..1e6b66efe8f51c75e757b7c5065e4e5e91eeecc4 100644
--- a/lib/dom/templates/dom/native/cpp_derived_sources.template
+++ b/lib/compiler/implementation/dart_backend/dart_backend.dart
@@ -2,8 +2,9 @@
 // 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.
 
-// WARNING: Do not edit - generated code.
+#library('dart_backend');
 
-#define NO_IMPLICIT_ATOMICSTRING
+#import('../leg.dart');
+#import('../tree/tree.dart');
 
-$INCLUDES
+#source('backend.dart');