Deprecate all diagnostics methods that use strings.

pkg/front_end/lib/src/fasta/builder/builder.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.builder;
 
-import '../errors.dart' show internalError;
+import '../deprecated_problems.dart' show deprecated_internalProblem;
 
 export 'class_builder.dart' show ClassBuilder;
 
 export 'field_builder.dart' show FieldBuilder;
 
 export 'library_builder.dart' show LibraryBuilder;
 
 export 'procedure_builder.dart' show ProcedureBuilder;
 
 export 'type_builder.dart' show TypeBuilder;
@@ skipping 19 matching lines @@
 export '../source/unhandled_listener.dart' show Unhandled;
 
 export 'member_builder.dart' show MemberBuilder;
 
 export 'modifier_builder.dart' show ModifierBuilder;
 
 export 'prefix_builder.dart' show PrefixBuilder;
 
 export 'invalid_type_builder.dart' show InvalidTypeBuilder;
 
-export '../scope.dart' show AccessErrorBuilder, Scope, ScopeBuilder;
+export '../scope.dart' show deprecated_AccessErrorBuilder, Scope, ScopeBuilder;
 
 export 'builtin_type_builder.dart' show BuiltinTypeBuilder;
 
 export 'dynamic_type_builder.dart' show DynamicTypeBuilder;
 
 export 'void_type_builder.dart' show VoidTypeBuilder;
 
 export 'function_type_builder.dart' show FunctionTypeBuilder;
 
 import 'library_builder.dart' show LibraryBuilder;
@@ skipping 59 matching lines @@
   bool get isConstructor => false;
 
   bool get isFactory => false;
 
   bool get isLocal => false;
 
   bool get isConst => false;
 
   bool get isSynthetic => false;
 
-  get target => internalError("Unsupported operation $runtimeType.");
+  get target =>
+      deprecated_internalProblem("Unsupported operation $runtimeType.");
 
   bool get hasProblem => false;
 
   String get fullNameForErrors;
 
   Uri computeLibraryUri() {
     Builder builder = this;
     do {
       if (builder is LibraryBuilder) return builder.uri;
       builder = builder.parent;
     } while (builder != null);
-    return internalError("No library parent.");
+    return deprecated_internalProblem("No library parent.");
   }
 
   void prepareInitializerInference(
       SourceLibraryBuilder library, ClassBuilder currentClass) {}
 }