Use ASTVisitor as in new AST.

compiler/java/com/google/dart/compiler/LibraryDepsVisitor.java

Index: compiler/java/com/google/dart/compiler/LibraryDepsVisitor.java
diff --git a/compiler/java/com/google/dart/compiler/LibraryDepsVisitor.java b/compiler/java/com/google/dart/compiler/LibraryDepsVisitor.java
index e66601aff7894a0095673832ee60c05a95dfc371..1b890f49f3e665e6bb0441b708202250eaf7bf54 100644
--- a/compiler/java/com/google/dart/compiler/LibraryDepsVisitor.java
+++ b/compiler/java/com/google/dart/compiler/LibraryDepsVisitor.java
@@ -6,7 +6,7 @@ package com.google.dart.compiler;
 import com.google.dart.compiler.ast.DartClass;
 import com.google.dart.compiler.ast.DartIdentifier;
 import com.google.dart.compiler.ast.DartNode;
-import com.google.dart.compiler.ast.DartNodeTraverser;
+import com.google.dart.compiler.ast.ASTVisitor;
 import com.google.dart.compiler.ast.DartParameterizedTypeNode;
 import com.google.dart.compiler.ast.DartPropertyAccess;
 import com.google.dart.compiler.ast.DartTypeNode;
@@ -23,7 +23,7 @@ import java.net.URI;
 /**
  * A visitor that fills in {@link LibraryDeps} for a compilation unit.
  */
-public class LibraryDepsVisitor extends DartNodeTraverser<Void> {
+public class LibraryDepsVisitor extends ASTVisitor<Void> {
   /**
    * Fill in {@link LibraryDeps} from a {@link DartUnit}.
    */