Issue 3931. Visit children nodes safely.

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

Index: compiler/java/com/google/dart/compiler/ast/DartSuperConstructorInvocation.java
diff --git a/compiler/java/com/google/dart/compiler/ast/DartSuperConstructorInvocation.java b/compiler/java/com/google/dart/compiler/ast/DartSuperConstructorInvocation.java
index 288e4fc2729b54a02acd0ee4ac82583fcd485647..ddf3a0e870f1b249c8576cfb36c35a4db9270c71 100644
--- a/compiler/java/com/google/dart/compiler/ast/DartSuperConstructorInvocation.java
+++ b/compiler/java/com/google/dart/compiler/ast/DartSuperConstructorInvocation.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.
 
@@ -49,9 +49,7 @@ public class DartSuperConstructorInvocation extends DartInvocation {
 
   @Override
   public void visitChildren(ASTVisitor<?> visitor) {
-    if (name != null) {
-      name.accept(visitor);
-    }
+    safelyVisitChild(name, visitor);
     visitor.visit(getArguments());
   }