Emit to StreamCodeOutput instead of CodeBuffer.

pkg/compiler/lib/src/js_emitter/js_emitter.dart

 // Copyright (c) 2013, 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 dart2js.js_emitter;
 
+import 'dart:async';
+
 import '../common.dart';
 
 import '../constants/expressions.dart';
 import '../constants/values.dart';
 
 import '../closure.dart' show
     ClosureClassElement,
     ClosureClassMap,
     ClosureFieldElement,
     CapturedVariable;
 
 import '../dart_types.dart' show
     TypedefType;
 
-import '../io/code_output.dart' show
-    CodeBuffer;
+import '../io/code_output.dart';
 
 import '../elements/elements.dart' show
     ConstructorBodyElement,
     ElementKind,
     FieldElement,
     ParameterElement,
     TypeVariableElement;
 
 import '../hash/sha1.dart' show hashOfString;
 
-// import '../helpers/helpers.dart';  // Included for debug helpers.
+import '../helpers/helpers.dart';  // Included for debug helpers.
 
 import '../js/js.dart' as jsAst;
 import '../js/js.dart' show
     js;
 
 import '../js_backend/js_backend.dart' show
     CheckedModeHelper,
     ConstantEmitter,
     CustomElementsAnalysis,
     JavaScriptBackend,
     JavaScriptConstantCompiler,
     Namer,
     NativeEmitter,
     RuntimeTypes,
     Substitution,
     TypeCheck,
     TypeChecks,
     TypeVariableHandler;
 
 import 'model.dart';
 import 'program_builder.dart';
 
 import 'new_emitter/emitter.dart' as new_js_emitter;
 
-import '../source_file.dart' show
-    SourceFile,
-    StringSourceFile;
+import '../io/line_column_provider.dart' show
+    LineColumnCollector,
+    LineColumnProvider;
 
 import '../io/source_map_builder.dart' show
     SourceMapBuilder;
 
 import '../util/characters.dart' show
     $$,
     $A,
     $HASH,
     $PERIOD,
     $Z,
@@ skipping 29 matching lines @@
 part 'old_emitter/class_emitter.dart';
 part 'old_emitter/code_emitter_helper.dart';
 part 'old_emitter/container_builder.dart';
 part 'old_emitter/declarations.dart';
 part 'old_emitter/emitter.dart';
 part 'old_emitter/interceptor_emitter.dart';
 part 'old_emitter/metadata_emitter.dart';
 part 'old_emitter/nsm_emitter.dart';
 part 'old_emitter/reflection_data_parser.dart';
 part 'old_emitter/type_test_emitter.dart';