Base JavaScript code position computation on JavaScript tracer.

pkg/compiler/lib/src/js/js_source_mapping.dart

 // Copyright (c) 2015, 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 js.source_mapping;
 
 import 'js.dart';
-import '../io/code_output.dart' show SourceLocations;
+import '../io/code_output.dart' show
+    BufferedCodeOutput,
+    CodeBuffer,
+    SourceLocations;
 import '../io/source_information.dart' show
     SourceLocation,
     SourceInformation,
     SourceInformationStrategy;
 
 /// [SourceInformationStrategy] that can associate source information with
 /// JavaScript output.
 class JavaScriptSourceInformationStrategy
     extends SourceInformationStrategy {
   const JavaScriptSourceInformationStrategy();
@@ skipping 38 matching lines @@
   }
 }
 
 /// A processor that associates [SourceInformation] with code position of
 /// JavaScript [Node]s.
 class SourceInformationProcessor extends CodePositionListener {
   const SourceInformationProcessor();
 
   /// Process the source information and code positions for the [node] and all
   /// its children.
-  void process(Node node) {}
+  void process(Node node, BufferedCodeOutput code) {}
 }