Remove deprecated_addNit.

pkg/front_end/lib/src/fasta/builder/class_builder.dart

Index: pkg/front_end/lib/src/fasta/builder/class_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/builder/class_builder.dart b/pkg/front_end/lib/src/fasta/builder/class_builder.dart
index f3cd77a21662820beb1546cb6e0dcb9ff9ef858f..edccd168c6835bfed2ffba690d298bc87f149737 100644
--- a/pkg/front_end/lib/src/fasta/builder/class_builder.dart
+++ b/pkg/front_end/lib/src/fasta/builder/class_builder.dart
@@ -229,8 +229,4 @@ abstract class ClassBuilder<T extends TypeBuilder, R>
   void deprecated_addWarning(int charOffset, String message) {
     library.deprecated_addWarning(charOffset, message, fileUri: fileUri);
   }
-
-  void deprecated_addNit(int charOffset, String message) {
-    library.deprecated_addNit(charOffset, message, fileUri: fileUri);
-  }
 }