dart2js: Move metadata from old_emitter to shared directory.

pkg/compiler/lib/src/js_emitter/metadata_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.
 
 part of dart2js.js_emitter;
 
 class MetadataEmitter extends CodeEmitterHelper {
   /// A list of JS expressions that represent metadata, parameter names and
   /// type, and return types.
   final List<String> globalMetadata = [];
@@ skipping 85 matching lines @@
     return addGlobalMetadata('"$name"');
   }
 
   int addGlobalMetadata(String string) {
     return globalMetadataMap.putIfAbsent(string, () {
       globalMetadata.add(string);
       return globalMetadata.length - 1;
     });
   }
 
-  void emitMetadata(CodeOutput output) {

[floitsch, 2015/01/29 14:36:30]

Moved to the oldEmitter.

-    String metadataAccess = emitter.generateEmbeddedGlobalAccessString(
-          embeddedNames.METADATA);
-    output.add('$metadataAccess$_=$_[');
-    for (String metadata in globalMetadata) {
-      if (metadata is String) {
-        if (metadata != 'null') {
-          output.add(metadata);
-        }
-      } else {
-        throw 'Unexpected value in metadata: ${Error.safeToString(metadata)}';
-      }
-      output.add(',$n');
-    }
-    output.add('];$n');
-  }
-
   List<int> computeMetadata(FunctionElement element) {
     return compiler.withCurrentElement(element, () {
       if (!mustEmitMetadataFor(element)) return const <int>[];
       List<int> metadata = <int>[];
       Link link = element.metadata;
       // TODO(ahe): Why is metadata sometimes null?
       if (link != null) {
         for (; !link.isEmpty; link = link.tail) {
           metadata.add(reifyMetadata(link.head));
         }
       }
       return metadata;
     });
   }
 }