Implement line and column numbers.

pkg/front_end/lib/src/fasta/dill/dill_target.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.dill_target;
 
 import 'dart:async' show
     Future;
 
 import 'package:kernel/ast.dart' show
@@ skipping 27 matching lines @@
 
 class DillTarget extends TargetImplementation {
   bool isLoaded = false;
   DillLoader loader;
 
   DillTarget(Ticker ticker, TranslateUri uriTranslator)
       : super(ticker, uriTranslator) {
     loader = new DillLoader(this);
   }
 
+  void addLineStarts(Uri uri, List<int> lineStarts) {
+    internalError("Unsupported operation.");
+  }
+
   void read(Uri uri) {
     if (loader.input == null) {
       loader.input = uri;
     } else {
       inputError(uri, -1, "Can only read one dill file.");
     }
   }
 
   Future<Null> writeProgram(Uri uri, AstKind kind) {
     return internalError("not implemented.");
@@ skipping 18 matching lines @@
   }
 
   void breakCycle(ClassBuilder cls) {
   }
 
   Class get objectClass {
     KernelClassBuilder builder = loader.coreLibrary.exports["Object"];
     return builder.cls;
   }
 }