Issue 6770. Support for @deprecated on library directive.

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

Index: compiler/java/com/google/dart/compiler/ast/DartDirective.java
diff --git a/compiler/java/com/google/dart/compiler/ast/DartDirective.java b/compiler/java/com/google/dart/compiler/ast/DartDirective.java
index ad1a9ecac3d647fa2f21ae7eb8844b723ce7a050..7c039c1d51f4aa325a82161c317f14d67cbcc304 100644
--- a/compiler/java/com/google/dart/compiler/ast/DartDirective.java
+++ b/compiler/java/com/google/dart/compiler/ast/DartDirective.java
@@ -1,4 +1,4 @@
-// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
+// 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.
 
@@ -9,9 +9,19 @@ import com.google.dart.compiler.resolver.NodeElement;
 /**
  * Base class for directives.
  */
-public abstract class DartDirective extends DartNodeWithMetadata {
+public abstract class DartDirective extends DartNodeWithMetadata implements HasObsoleteMetadata {
+  private DartObsoleteMetadata obsoleteMetadata = DartObsoleteMetadata.EMPTY;
+
   @Override
   public NodeElement getElement() {
     throw new UnsupportedOperationException(getClass().getSimpleName());
   }
+
+  public DartObsoleteMetadata getObsoleteMetadata() {
+    return obsoleteMetadata;
+  }
+
+  public void setObsoleteMetadata(DartObsoleteMetadata metadata) {
+    this.obsoleteMetadata = metadata;
+  }
 }