Remove deprecated_addNit.

pkg/front_end/lib/src/fasta/kernel/fasta_accessors.dart

 // Copyright (c) 2016, 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.
 
 library fasta.fasta_accessors;
 
 import 'package:kernel/ast.dart'
     hide InvalidExpression, InvalidInitializer, InvalidStatement;
 
 import '../../scanner/token.dart' show Token;
@@ skipping 105 matching lines @@
 
   bool isIdentical(Member member);
 
   Expression buildMethodInvocation(
       Expression receiver, Name name, Arguments arguments, int offset,
       {bool isConstantExpression, bool isNullAware, bool isImplicitCall});
 
   DartType validatedTypeVariableUse(
       TypeParameterType type, int offset, bool nonInstanceAccessIsError);
 
+  void warning(Message message, int charOffset);
+
   void deprecated_warning(String message, [int charOffset]);
 
   void warnUnresolvedSuperGet(Name name, int charOffset);
 
   void warnUnresolvedSuperSet(Name name, int charOffset);
 
   void warnUnresolvedSuperMethod(Name name, int charOffset);
 }
 
 abstract class FastaAccessor implements Accessor {
@@ skipping 813 matching lines @@
 
   TypeDeclarationAccessor(BuilderHelper helper, this.declaration,
       String plainNameForRead, Token token)
       : super(helper, null, plainNameForRead, token);
 
   Expression get expression {
     if (super.expression == null) {
       int offset = offsetForToken(token);
       if (declaration is KernelInvalidTypeBuilder) {
         KernelInvalidTypeBuilder declaration = this.declaration;
-        String message = declaration.message;
-        helper.library.deprecated_addWarning(declaration.charOffset, message,
-            fileUri: declaration.fileUri);
-        helper.deprecated_warning(message, offset);
+        helper.library.addWarning(
+            declaration.message, declaration.charOffset, declaration.fileUri);
+        helper.warning(declaration.message, offset);
         super.expression = new Throw(
-            new StringLiteral(message)..fileOffset = offsetForToken(token))
+            new StringLiteral(declaration.message.message)
+              ..fileOffset = offsetForToken(token))
           ..fileOffset = offset;
       } else {
         super.expression = new KernelTypeLiteral(
             buildType(null, nonInstanceAccessIsError: true))
           ..fileOffset = offsetForToken(token);
       }
     }
     return super.expression;
   }
 
@@ skipping 81 matching lines @@
     offset ??= offsetForToken(this.token);
     return helper.throwNoSuchMethodError(new NullLiteral()..fileOffset = offset,
         plainNameForRead, arguments, offset,
         isGetter: isGetter, isSetter: isSetter);
   }
 }
 
 bool isFieldOrGetter(Member member) {
   return member is Field || (member is Procedure && member.isGetter);
 }