Revert "Store actual Reference(s) for additional exports."

pkg/kernel/lib/binary/ast_from_binary.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 kernel.ast_from_binary;
 
 import 'dart:convert';
 import 'dart:typed_data';
 
 import '../ast.dart';
 import '../transformations/flags.dart';
@@ skipping 369 matching lines @@
     }
 
     debugPath.add(library.name ?? library.importUri?.toString() ?? 'library');
 
     if (shouldWriteData) {
       _fillTreeNodeList(library.annotations, readExpression, library);
     } else {
       _skipNodeList(readExpression);
     }
     _readLibraryDependencies(library);
-    _readAdditionalExports(library);
     _readLibraryParts(library);
     _mergeNamedNodeList(library.typedefs, readTypedef, library);
     _mergeNamedNodeList(library.classes, readClass, library);
     _mergeNamedNodeList(library.fields, readField, library);
     _mergeNamedNodeList(library.procedures, readProcedure, library);
 
     debugPath.removeLast();
     _currentLibrary = null;
     return library;
   }
@@ skipping 10 matching lines @@
       var annotations = readExpressionList();
       var targetLibrary = readLibraryReference();
       var prefixName = readStringOrNullIfEmpty();
       var names = readCombinatorList();
       library.dependencies[i] = new LibraryDependency.byReference(
           flags, annotations, targetLibrary, prefixName, names)
         ..parent = library;
     }
   }
 
-  void _readAdditionalExports(Library library) {
-    int numExportedReference = readUInt();
-    if (numExportedReference != 0) {
-      for (int i = 0; i < numExportedReference; i++) {
-        CanonicalName exportedName = readCanonicalNameReference();
-        Reference reference = exportedName.getReference();
-        library.additionalExports.add(reference);
-      }
-    }
-  }
-
   Combinator readCombinator() {
     var isShow = readUInt() == 1;
     var names = readStringReferenceList();
     return new Combinator(isShow, names);
   }
 
   List<Combinator> readCombinatorList() {
     return new List<Combinator>.generate(readUInt(), (i) => readCombinator());
   }
 
@@ skipping 851 matching lines @@
       ..fileOffset = offset
       ..fileEqualsOffset = fileEqualsOffset;
   }
 
   int readOffset() {
     // Offset is saved as unsigned,
     // but actually ranges from -1 and up (thus the -1)
     return readUInt() - 1;
   }
 }