Serialize WarnOnUseElement

pkg/compiler/lib/src/serialization/equivalence.dart

Index: pkg/compiler/lib/src/serialization/equivalence.dart
diff --git a/pkg/compiler/lib/src/serialization/equivalence.dart b/pkg/compiler/lib/src/serialization/equivalence.dart
index 6f86c3c0fe84f834c85d838739739ce7e35a39e4..6cb175cc6d9227bdce9430d57531fb3b4ca226c4 100644
--- a/pkg/compiler/lib/src/serialization/equivalence.dart
+++ b/pkg/compiler/lib/src/serialization/equivalence.dart
@@ -523,6 +523,13 @@ class ElementIdentityEquivalence extends BaseElementVisitor<bool, Element> {
     return strategy.test(element1, element2, 'messageKind',
         element1.messageKind, element2.messageKind);
   }
+
+  @override
+  bool visitWarnOnUseElement(
+      WarnOnUseElement element1, WarnOnUseElement element2) {
+    return strategy.testElements(element1, element2, 'wrappedElement',
+        element1.wrappedElement, element2.wrappedElement);
+  }
 }
 
 /// Visitor that checks for equivalence of [DartType]s.