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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 3acb1029dda6748c242c7b3cd0f392f12026e033..6f86c3c0fe84f834c85d838739739ce7e35a39e4 100644
--- a/pkg/compiler/lib/src/serialization/equivalence.dart
+++ b/pkg/compiler/lib/src/serialization/equivalence.dart
@@ -516,6 +516,13 @@ class ElementIdentityEquivalence extends BaseElementVisitor<bool, Element> {
             element1, element2, 'name', element1.name, element2.name) &&
         visit(element1.library, element2.library);
   }
+
+  @override
+  bool visitErroneousElement(
+      ErroneousElement element1, ErroneousElement element2) {
+    return strategy.test(element1, element2, 'messageKind',
+        element1.messageKind, element2.messageKind);
+  }
 }
 
 /// Visitor that checks for equivalence of [DartType]s.