Issue 3931. Visit children nodes safely.

compiler/java/com/google/dart/compiler/ast/DartRedirectConstructorInvocation.java

Index: compiler/java/com/google/dart/compiler/ast/DartRedirectConstructorInvocation.java
diff --git a/compiler/java/com/google/dart/compiler/ast/DartRedirectConstructorInvocation.java b/compiler/java/com/google/dart/compiler/ast/DartRedirectConstructorInvocation.java
index 3cc1e59e261dbcea3aa32b4025510c6c9e6cc7c1..3697326cd283c71a4c98d3b6a389137e21064fcb 100644
--- a/compiler/java/com/google/dart/compiler/ast/DartRedirectConstructorInvocation.java
+++ b/compiler/java/com/google/dart/compiler/ast/DartRedirectConstructorInvocation.java
@@ -1,4 +1,4 @@
-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2012, 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.
 
@@ -38,9 +38,7 @@ public class DartRedirectConstructorInvocation extends DartInvocation {
 
   @Override
   public void visitChildren(ASTVisitor<?> visitor) {
-    if (name != null) {
-      name.accept(visitor);
-    }
+    safelyVisitChild(name, visitor);
     visitor.visit(getArguments());
   }