Issue 839: Bad code leading to top level methods being something other than identifier

compiler/java/com/google/dart/compiler/ast/viz/NullWriter.java

Index: compiler/java/com/google/dart/compiler/ast/viz/NullWriter.java
diff --git a/compiler/java/com/google/dart/compiler/ast/viz/NullWriter.java b/compiler/java/com/google/dart/compiler/ast/viz/NullWriter.java
new file mode 100644
index 0000000000000000000000000000000000000000..49c3c5c183b965da451c365bc357d49d0735f72c
--- /dev/null
+++ b/compiler/java/com/google/dart/compiler/ast/viz/NullWriter.java
@@ -0,0 +1,35 @@
+// Copyright (c) 2011, 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.
+
+package com.google.dart.compiler.ast.viz;
+
+import com.google.dart.compiler.ast.DartNode;
+import com.google.dart.compiler.ast.DartUnit;
+
+/**
+ * Write the AST in Dot format. Output file is placed next to the JS file in the output directory
+ */
+public class NullWriter extends BaseASTWriter {
+
+  public NullWriter(String outputDir) {
+    super(outputDir);
+  }
+
+  @Override
+  protected void startHook(DartUnit unit) {
+  }
+
+  @Override
+  protected void endHook(DartUnit unit) {
+  }
+
+  @Override
+  public void process(DartUnit unit) {
+    return;
+  }
+
+  @Override
+  protected void write(String nodeType, DartNode node, String data) {
+  }
+}