Store actual Reference(s) for additional exports.

pkg/front_end/lib/src/fasta/source/source_library_builder.dart

Index: pkg/front_end/lib/src/fasta/source/source_library_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/source/source_library_builder.dart b/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
index cfbb348487164abadefee701b5bcd32338adfc03..b3210f98ac862ffb38229f13465e7e3ef25a28bd 100644
--- a/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
+++ b/pkg/front_end/lib/src/fasta/source/source_library_builder.dart
@@ -54,8 +54,6 @@ import '../import.dart' show Import;
 
 import '../problems.dart' show unhandled;
 
-import '../util/relativize.dart' show relativizeUri;
-
 import 'source_loader.dart' show SourceLoader;
 
 abstract class SourceLibraryBuilder<T extends TypeBuilder, R>
@@ -99,11 +97,16 @@ abstract class SourceLibraryBuilder<T extends TypeBuilder, R>
 
   bool canAddImplementationBuilders = false;
 
-  /// Exports in addition to the members declared in this library.
+  /// Exports that can't be serialized.
+  ///
+  /// The key is the name of the exported member.
   ///
-  /// See [../dill/dill_library_builder.dart] for additional details on the
-  /// format used.
-  List<List<String>> additionalExports;
+  /// If the name is `dynamic` or `void`, this library reexports the
+  /// corresponding type from `dart:core`, and the value is null.
+  ///
+  /// Otherwise, this represents an error (an ambiguous export). In this case,
+  /// the error message is the corresponding value in the map.
+  Map<String, String> additionalExports;
 
   SourceLibraryBuilder(SourceLoader loader, Uri fileUri)
       : this.fromScopes(loader, fileUri, new DeclarationBuilder<T>.library(),
@@ -524,17 +527,20 @@ abstract class SourceLibraryBuilder<T extends TypeBuilder, R>
     }
     exportScope.forEach((String name, Builder member) {
       if (member.parent != this) {
-        additionalExports ??= <List<String>>[];
-        Builder parent = member.parent;
-        if (parent is LibraryBuilder) {
-          additionalExports.add(<String>[
-            relativizeUri(parent.uri, base: uri.resolve(".")),
-            name
-          ]);
-        } else {
-          InvalidTypeBuilder invalidType = member;
-          String message = invalidType.message.message;
-          additionalExports.add(<String>[null, name, message]);
+        switch (name) {
+          case "dynamic":
+          case "void":
+            additionalExports ??= <String, String>{};
+            additionalExports[name] = null;
+            break;
+
+          default:
+            if (member is InvalidTypeBuilder) {
+              additionalExports ??= <String, String>{};
+              additionalExports[name] = member.message.message;
+            } else {
+              target.additionalExports.add(member.target.reference);

[ahe, 2017/09/01 14:05:39]

I had to move this to kernel_library_builder.dart, which highlights again that
Konstantin is right about that the hierarchy is too complicated.

+            }
         }
       }
     });