dart2js: Remove oldEmitter field in emitter-task.

pkg/compiler/lib/src/dump_info.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 dump_info;
 
 import 'dart:convert' show
     HtmlEscape,
     JsonEncoder,
     StringConversionSink,
     ChunkedConversionSink;
 
 import 'elements/elements.dart';
 import 'elements/visitor.dart';
 import 'dart2jslib.dart' show
     Backend,
     CodeBuffer,
     Compiler,
     CompilerTask,
     MessageKind;
 import 'types/types.dart' show TypeMask;
 import 'deferred_load.dart' show OutputUnit;
 import 'js_backend/js_backend.dart' show JavaScriptBackend;
+import 'js_emitter/js_emitter.dart' show OldEmitter;
 import 'js/js.dart' as jsAst;
 import 'universe/universe.dart' show Selector, UniverseSelector;
 import 'util/util.dart' show NO_LOCATION_SPANNABLE;
 
 /// Maps objects to an id.  Supports lookups in
 /// both directions.
 class IdMapper<T>{
   Map<int, T> _idToElement = {};
   Map<T, int> _elementToId = {};
   int _idCounter = 0;
@@ skipping 555 matching lines @@
               });
           }
         }
       }
     }
 
     List<Map<String, dynamic>> outputUnits =
         new List<Map<String, dynamic>>();
 
     JavaScriptBackend backend = compiler.backend;
+    // Dump-info currently only works with the full emitter. If another
+    // emitter is used it will fail here.
+    OldEmitter fullEmitter = backend.emitter.emitter;
 
     for (OutputUnit outputUnit in
         infoCollector.mapper._outputUnit._elementToId.keys) {
       String id = infoCollector.mapper._outputUnit.add(outputUnit);
       outputUnits.add(<String, dynamic> {
         'id': id,
         'name': outputUnit.name,
-        'size': backend.emitter.oldEmitter.outputBuffers[outputUnit].length,
+        'size': fullEmitter.outputBuffers[outputUnit].length,
       });
     }
 
     Map<String, dynamic> outJson = {
       'elements': infoCollector.toJson(),
       'holding': holding,
       'outputUnits': outputUnits,
       'dump_version': 3,
       'deferredFiles': compiler.deferredLoadTask.computeDeferredMap(),
       // This increases when new information is added to the map, but the viewer
@@ skipping 17 matching lines @@
     ChunkedConversionSink<Object> sink =
       encoder.startChunkedConversion(
           new StringConversionSink.fromStringSink(buffer));
     sink.add(outJson);
     compiler.reportInfo(NO_LOCATION_SPANNABLE,
         const MessageKind(
             "View the dumped .info.json file at "
             "https://dart-lang.github.io/dump-info-visualizer"));
   }
 }