Use ASTVisitor as in new AST.

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

Index: compiler/java/com/google/dart/compiler/ast/DartExprStmt.java
diff --git a/compiler/java/com/google/dart/compiler/ast/DartExprStmt.java b/compiler/java/com/google/dart/compiler/ast/DartExprStmt.java
index 40c7a9fcedfe7f6b8228b457e8352c3298d7572f..2cc10ca4c7c72965d0e670d13b2a33f27fb4625d 100644
--- a/compiler/java/com/google/dart/compiler/ast/DartExprStmt.java
+++ b/compiler/java/com/google/dart/compiler/ast/DartExprStmt.java
@@ -19,20 +19,13 @@ public class DartExprStmt extends DartStatement {
     return expr;
   }
 
-  public void traverse(DartVisitor v, DartContext ctx) {
-    if (v.visit(this, ctx)) {
-      expr =  becomeParentOf(v.accept(expr));
-    }
-    v.endVisit(this, ctx);
-  }
-
   @Override
-  public void visitChildren(DartPlainVisitor<?> visitor) {
+  public void visitChildren(ASTVisitor<?> visitor) {
     expr.accept(visitor);
   }
 
   @Override
-  public <R> R accept(DartPlainVisitor<R> visitor) {
+  public <R> R accept(ASTVisitor<R> visitor) {
     return visitor.visitExprStmt(this);
   }
 }